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ACID BASE AND SALT

from Femosky110 on 06/12/2020 01:18 PM

ACID BASE AND SALTS
Various definitions of Acids and Bases

 

There are various definitions of acids and bases. Although these definitions don't disagree with one another, they differ in their comprehensiveness. Apart from the already established definitions of Acids, bases and salts Antoine Lavoisier, Humphry Davy, and Justus Liebig as well discovered few things about acids and bases, but they didn't make their definitions formal.

Svante Arrhenius defined acid in terms of their behavior in water.

In 1884 Svante Arrhenius observed that salts like NaCl dissociate in water to provide particles he called ions.

H2O

NaCl(s) Na+(aq) + Cl-(aq)

3 years after that he extended his theory by explaining that acids are neutral compounds that ionize when they dissolve in water to give H+ ions and an equivalent negative ion. His theory describes hydrogen chloride as an acid because it ionizes in aqueous solution to produce hydrogen (H+) and chloride (Cl-) ions as s demonstrated below:

H2O

HCl(g) H+(aq) + Cl-(aq)

In summary, his theory of acids states that:

• Acids are compounds which generate H+ ions in aqueous solutions eg.

• Bases are compounds which generate OH- ions in aqueous solutions

• His definition only works in the presence of water. The definition is only valid in aqueous solutions.

• His definition only allows protic acids that are able to produce hydrogen ions

The definition also only allows hydroxide bases.

Arrhenius also dispute that bases are neutral compounds that also dissociate or ionize in water to produce OH- ions and a positive ion. NaOH is an example of Arrhenius base due to the fact that it dissociates in water to give the hydroxide (OH-) and sodium (Na+) ions.

H2O

NaOH(s) Na+(aq) + OH-(aq)

An Arrhenius acid is therefore any material that ionizes when dissolved in water to produce the H+, or hydrogen ion.

An Arrhenius base is therefore any material that produces the OH-, or hydroxide, ion when dissolved in water.

Examples of Arrhenius acids are compounds like HCl, HCN, and H2SO4 that ionize in water to produce H+ ion. Examples of Arrhenius bases are ionic compounds that have the OH- ion, like NaOH, KOH, and Ca(OH)2.

The Arrhenius theory explains the reason why acids posses related properties. The distinguishing properties of acids are as a result of the presence of the H+ ion produced when an acid is dissolved in water. It also gives explanation to why acids neutralize bases and why bases neutralize acids. Acids supply the H+ ion; bases supply the OH- ion; and these two ions join together to form water.

H+(aq) + OH-(aq) H2O(l)

Disadvantages of the Arrhenius theory
1. It can be relevant only to reactions that take place in water because it defines acids and bases in terms of their behavior when dissolved in water.

2. It gives no explanation to why a number of compounds that has hydrogen with an oxidation number of +1 like HCl dissolve in water to yield acidic solutions, while others like CH4 don't.

3. It is just the compounds that hold the OH- ion that are graded as Arrhenius bases. The Arrhenius theory does not give explanation to why compounds like Na2CO3 have the distinguishing properties of bases.

Johannin es Nicolaus Brønsted - Thomas Martin Lowry theory of acid defined acids as

• Proton donors and

• Bases as proton acceptors

• The definition also works in aqueous solutions

• The definition works for bases apart from hydroxide bases.

• The definition only allows protic acids.

Gilbert Newton Lewis defined
• Acids as electron pair acceptors

• Bases as electron pair donors

Properties of Acids
1. Acid tastes sour and must not be tasted.

2. Acids turn blue litmus paper to red.

3. Aqueous solutions of acids conduct electric current. They are therefore good electrolytes

4. Acids react with bases to form salts and water

5. Acids give out hydrogen gas when they are reacted with an active metal like alkali metals, alkaline earth metals, zinc and aluminum.

Properties of Bases
1. Bases taste bitter and must not be tasted

2. They sense slippery or foamy. You must not by chance feel them

3. Bases don't alter the color of litmus paper but can they can turn red or acidified litmus paper to blue

4. Aqueous solutions of bases conduct electricity and are therefore good electrolytes.

5. Bases react with acids to form salts and water

Examples of regular Acids
• Citric acid from particular fruits and vegetables especially citrus fruits

• ascorbic acid-vitamin C from as from certain fruits

• vinegar which contains about 5% acetic acid

• carbonic acid that are useful during the carbonation process of soft drinks

• lactic acid is available in buttermilk

Examples of regular Bases
• Detergents

• Soap

• Soduim hydroxide (NaOH)

• Aqueous ammonia

pH and pH Meter
In chemistry, pH is an evaluation of the acidity or basicity of an aqueous solution. Solutions that have a pH value that is below 7 are said to be acidic and solutions that have pH value greater than 7 are considered basic or alkaline. The pH of pure water is about 7.

Acid-Base Indicators
Weak Acids and Bases can be used as Acid-Base indicator. An acid-base indicator is a weak acid or a weak base. An Indicator acid base indicator does not change color from pure acid to pure alkali solution at particular hydrogen ion concentration, but to a certain extent, color change takes place over a range of hydrogen ion concentrations. This range is termed the color change interval and is articulated as a pH range.

The use of acid base indicators

Weak acids are titrated in the presence of indicators that alter a little in alkaline situations. Weak bases ought to be titrated in the presence of indicators that alter their colours under a little acidic condition.

Popular acid-base indicators:

Examples of acid-base indicators are:

• Thymol blue

• tropeolin OO

• methyl yellow

• methyl orange

• bromphenol blue

• bromcresol green

• methyl red

• bromthymol blue

• phenol red

• neutral red

• phenolphthalein

• thymolphthalein

• alizarin yellow

• tropeolin O

• nitramin

• trinitrobenzoic acid.

Common Acid-Base Indicators
Indicator pH Range Qty per 10 ml Acid Base
Thymol Blue 1.2-2.8 1-2 drops 0.1% solution in aqueous red yellow
Pentamethoxy red 11.2-2.3 1 drop 0.1% soln. in 70% alcohol red-violet colorless
Tropeolin OO 1.3-3.2 1 drop 1% of aqueous solution red Yellow
Tropeolin OO 1.3-3.2 1 drop 1% of aqueous solution red Yellow
2,4-Dinitrophenol 2.4-4.0 1-2 drops 0.1% solution in 50% alcohol colourless Yellow
Methyl yellow 2.9-4.0 1 drop 0.1% solution in 90% alcohol red Yellow
Methyl orange 3.1-4.4 1 drop 0.1% aqueous solution red Orange
Bromphenol blue 3.0-4.6 1 drop 0.1% aqueous solution yellow blue-violet
Tetrabromphenol blue 3.0-4.6 1 drop 0.1% aqueous solution yellow blue
Alizarin sodium sulfonate 3.7-5.2 1 drop 0.1% aqueous soln yellow Violet
α-Naphthyl red 3.7-5.0 1 drop 0.1% solution in 70% alcohol red Yellow
p-Ethoxychrysoidine 3.5-5.5 1 drop 0.1% aqueous solution red Yellow
Hydrolysis
Hydrolysis is a chemical reaction that results to molecules of water (H2O) being divided into hydrogen cations H+ and hydroxide anions (OH−) in the process of a chemical reaction. The cation is usually known as protons. Hydrolysis is the kind of reaction that is used to break down definite polymers, principally those prepared by step-growth polymerization. Such dilapidation of polymer is frequently catalyzed by either acid or alkali example concentrated sulfuric acid (H2SO4) and sodium hydroxide (NaOH) respectively.

Types of hydrolysis
Hydrolysis is a chemical reaction in which a particular molecule is divided into two parts with the addition of one molecule of water. One part of the reacting molecule gains a hydrogen ion (H+) through the water molecule added. The remaining part takes up the other hydroxyl group (OH−).

The most widespread hydrolysis takes place when a salt of a weak acid or /and a weak base is dissolved in water. Water automatically ionizes into negative hydroxyl ions and positive hydrogen ions. The salt splits into positive and negative ions. For instance, sodium acetate in water dissociates into sodium and acetate ions. Sodium ions react sparingly with hydroxyl ions while acetate ions join with hydrogen ions to form neutral acetic acid, and the overall result is a comparative overload of hydroxyl ions, resulting to a basic solution.

Nevertheless, under standard conditions, just a small number of reactions occur between water and organic compounds. Commonly, strong acids or bases have to be incorporated to be able to attain hydrolysis where water has no consequence. The acid or base would act as a catalyst. They are used to hasten up a reaction but they remain unchanged at the end of the reaction.

Acid–base catalyzed hydrolyses reaction are extremely widespread. An instance is the hydrolysis of amides or esters. Their hydrolysis takes place when the nucleophile ie nucleus hunting agent, for example water or hydroxyl ion reacts with the carbon of the carbonyl group of the ester or amide. In an aqueous base solution, hydroxyl ions are more of better nucleophile than dipoles like water. In acid, the carbonyl group becomes protonated which results to a better nucleophilic attack. The products for the two types of hydrolysis reaction are compounds with carboxylic acid groups.

Acidic, Basic, and Neutral Salts

Some examples of Ions of Neutral Salts

Cations

Na+ + K+ Rb+ Cs+

Mg2+ Ca2+ Sr2+ Ba2+

Anions

Cl- Br- I-,

ClO4- BrO4- ClO3- N03-

A salt is a compound formed when an acid is reacted with a base. Normally, a neutral salt is formed when a strong acid neutralizes a strong base in the reaction. See example below:

H+ + OH- = H2O

The passerby ions in an acid-base reaction result into a salt solution. The majority of neutral salts contain cations and anions listed below: They have less affinity with water. Therefore, salts that contain any of these ions are neutral salts. For instance: NaCl, KNO3, CaBr2, CsClO4 are neutral salts.

Acidic Ions

NH4+ Al3+ Pb2+ Sn2+

Transition metal ions

HSO4- H2PO4-

Basic Ions

F- C2H3O2- NO2- HCO3-

CN- CO32- S2- SO42-

HPO42- PO43-

During a reaction between weak acids and bases, the comparative strength of the reacting acid-base pair in the salt establishes the pH of the solutions. The salt, or the solution of the salt formed can either be acidic, neutral or basic. Acid salt is formed between a strong acid and a weak eg. NH4Cl.Abasic salt is formed between a weak acid and a strong base .eg. NaCH3COO.

Hydrolysis of Acidic Salts
Acid salt is formed between a strong acid and a weak eg. NH4Cl. Ammonia is a weak base, and a salt of ammonia with every strong acid result to a solution with a pH below 7. For instance in the reaction between hydrocholic acid and ammonia below:

HCl + NH4OH = NH4+ + Cl- + H2O

Here, the NH4+ ion reacts with water through the process of hydrolysis as shown in the equation below:

NH4+ + H2O = NH3 + H3O+ .

The acidity constant can be obtined from Kw and Kb.

[H3O+] [NH3] [OH- ]

Ka = ---------------- ------

[NH4+] [OH-]

= Kw / Kb

= 1.00e-14 / 1.75e-5 = 5.7e-10. Where a =acid, b =base and w = water.

ENERGY AND ENERGY CHANGE

from Femosky110 on 06/12/2020 01:16 PM

Energy and Energy Changes
Chemical changes occur on the molecular level. A chemical change results in the formation of a new substance.

 

Examples of Chemical Changes include:

• Combustion or burning e.g. burning wood

• Dissolution of salt in water

• combination of acid and base

• digestion of food

• cooking of an egg,

• rusting of an iron or metal object

• Combination of hydrochloric acid and sodium hydroxide to produce salt and water.

Physical Changes
Physical changes deals with energy and states of matter. A physical change unlike the chemical change does not lead to the formation of a fresh substance. Changes in state such as melting, freezing, vaporization, condensation, sublimation are all physical changes.

Examples of physical changes include:

• crumpling a sheet of paper

• melting an ice cube

• casting silver in a mold

• breaking a bottle

• Crushing a can.

How to know a Chemical Change and a physical change

A chemical change results to the formation of a substance which was not there previously. You may be able to ascertain a chemical change through some indicators like light, heat, color alteration, gas formation, odor, or sound. The reactant and the product of a physical change are the same, although they may appear to be variable.

A physical change may have occurred if the changes that are associated with a chemical change are not found. It can be hard to tell this in some reactions such as when sugar is dissolved in water. In this case the content is still the same chemically although the sugar has dissolved. The sugar is now present in the mixture as molecules of sucrose .Nevertheless, when you dissolve salt in water, the salt dissociates into its ions of Na+ and Cl- resulting to a chemical change. In the two scenarios, a white solid (salt) is dissolved into a clear liquid and in the two scenarios the reactant can be recovered by taking away the water. Irrespective of this, the two reactions are different.

Endothermic and Exothermic Reactions
Scores of chemical reactions discharge energy in the form of heat, light, or sound. These types of reactions are termed exothermic reactions. Exothermic reactions may occur instinctively and lead to an increased randomness or entropy (ΔS > 0) of the reacting system. They are designated by a negative heat flow meaning that heat is expelled to the surroundings and decrease in enthalpy (ΔH < 0). Exothermic reactions generate heat and may be explosive when performed in the lab.

The second group of chemical reaction rather than give out heat to the surroundings absorbs heat from the surrounding in order to occur. These types of chemical reactions are referred to as endothermic reactions. Endothermic reactions are not spontaneous reactions. Work must be performed to be able to cause the reaction to take place. When endothermic reactions take up energy, a drop in temperature is calculated and noted on the course of the reaction. Endothermic reactions are denoted by positive heat flow and a rise in enthalpy (+ΔH).

Examples of Endothermic and Exothermic Processes
Photosynthesis is one example of an endothermic chemical reaction. During photosynthesis, plants make use of the energy obtained from the sun in the conversion of carbon dioxide and water into glucose and oxygen. The process of photosynthesis takes up 15MJ of energy (sunlight) in order to produce one kilogram of glucose as exemplified in the equation below:

Sunlight + 6CO2(g) + H2O(l) = C6H12O6(aq) + 6O2(g)

One example of an exothermic reaction is the reaction between sodium and chlorine to form table salt. The formation of the table salt reaction gives off 411 kJ of energy for one mole of salt formed as exemplified below:

Na(s) + 0.5Cl2(s) = NaCl(s)

Exothermic- The term exothermic explains the process that gives out energy in the form of heat.

Formation of a chemical bond usually leads to the release of an energy to the surrounding and can therefore be termed an exothermic process. Exothermic reactions frequently feel hot due to the fact that it is releasing energy to the surrounding.

Endothermic – is used to denote a process or reaction that absorbs energy in the form of heat before it could occur.

Breaking a chemical bond needs energy and is consequently regarded as Endothermic. Endothermic reactions frequently feel cold because they absorb heat from the surrounding.

Examples of exothermic Processes Examples of endothermic Processes

• freezing of water

• solidification of solid salts

• condensation of water vapor

• formation of a hydrate from an anhydrous salt

• formation of an anion from an atom in gaseous state

• Total destruction of matter E=mc2

• division of an atom

• melting of ice cubes

• melting of solid salts

• evaporation of liquid water

• production of an anhydrous salt from a hydrate

• producing a cation from an atom in the gaseous state

• breaking up of a gas molecule

• separation of ion pairs

• boiling of an egg

• baking of bread

Examples of Exothermic Reactions Examples of Endothermic Reactions

• burning of hydrogen

• liquefaction of lithium chloride in water

• combustion of propane

• drying out the moisture of sugar with sulfuric acid

• thermite

• disintegration of hydrogen peroxide

• disintegration of ammonium dichromate

• halogenation of acetylene

• Reaction of barium hydroxide octahydrate crystals with dry ammonium chloride

• melting ammonium chloride in water

• reacting thionyl chloride (SOCl2) with cobalt(II) sulfate heptahydrate

• mixture of water and ammonium nitrate

• mixture of water and potassium chloride

• reaction between ethanoic acid and sodium carbonate

• Photosynthesis (chlorophyll is used in the reaction of carbon dioxide, water and energy to produce glucose and oxygen.

Energy-level profile diagrams
An energy diagram can be employed to demonstrate the energy movements in these reactions and temperature can be made use of to evaluate them visibly.

Every chemical process is characterized by changes in the energy. Before a reaction could occur it can either release or absorb energy. Exothermic reactions usually occur spontaneously and make their surroundings to heat up. That is the entropy or disorder of the environment is increased.

The energy state of any chemical reaction can be denoted by Gibbs free energy.

The Enthalpy
Enthalpy is described in thermodynamics as an evaluation of the heat content of a chemical or physical system. Enthalpy (H) is an estimation of the total energy of a system and regularly denotes and demonstrates in a simpler way energy transfer between the reacting systems. A positive change in enthalpy denotes an endothermic reaction for the reason that energy is absorbed. A negative change in enthalpy denotes an exothermic reaction for the fact that the system has lost some energy to the environment.

The Entropy
A thermodynamic property that is the measure of a system's thermal energy per unit temperature that is unavailable for doing useful work.

The Free energy
The free energy of a reacting system is the difference between the internal energy of a system and the product of its entropy and absolute temperature.

Gibbs free energy
The difference between the enthalpy of a system and the product of its entropy plus absolute temperature is referred to as Gibbs free energy. It is a determination of the useful work obtained from a thermodynamic system at constant temperature and pressure.

chemistry
Heat
Heat is defined as the energy transferred from one system to another by thermal interaction.

Law of conservation of energy:

The law of the conservation of energy states that energy can neither be destroyed nor created but can be altered from one form to another. The total energy of a reacting system and the surroundings remains constant or unchanged.

Change in Enthalpy is the expression that is used to explain the energy swap over that occurs with the surroundings at a constant pressure. It is denoted with the symbol ΔH.

Enthalpy is the total energy content of the reactants. It is denoted with the symbol, H.

ΔH = ΔH products - ΔH reactants

The units of enthalpy are kilojoules per mole (kJmol-1)

An exothermic enthalpy change is constantly represented with a negative value, due to the fact that energy is expelled to the surroundings.

ΔH = -xkJmol-1

An endothermic enthalpy change is constantly represented with a positive value, since the energy is absorbed by the system from the surroundings.

ΔH = + ykJmol-1.

Standard enthalpy changes: standard conditions

When we want to place the enthalpy changes of different types of reactions side by side each other for comparison, we must make use of standard conditions like known temperatures, pressures, amounts and concentrations of reactants or products.

The standard conditions are listed below:

• A pressure of 100 kilopascals (102kPa)

• A temperature of 298K (25oC )

• Reactants and products in physical states, typical for conditions above.

• A concentration of 1.0mol dm-3 for solutions.

The o sign is used to denote a standard condition.

Standard enthalpy change of reaction

ΔHor

The standard enthalpy change of reaction is the enthalpy change of that reaction when the amounts of reactants shown in the equation for the reaction, react under standard conditions to form the products in their standard states.

Standard enthalpy change of formation

ΔHof

The standard enthalpy change of formation is the enthalpy change when one mole of a compound is formed from its constituent elements under standard conditions. This means that both compound and elements are in their standard states.

The Standard enthalpy change of combustion

ΔHoc

The standard enthalpy change of combustion is the enthalpy change when one mole of an element or compound is completely reacted with oxygen under standard conditions.

The Energy Content of Fuels

Energy content is a significant property of both food and matter that is made use of during the process of heating. The energy that our body utilizes for day to day activities like sleep, walk, talk etc comes from the food that we eat, for instance the candy bar. The energy that is generated a fuel is burned is a crucial quantity, and we'd like to be capable of measuring the effectiveness of fuel.

The energy content is the amount of heat produced by the combustion of 1 gram of a substance and is measured in joules per gram (J/g). Heat is a form of energy or in reality a flow of energy flow and it is usually calculated in calories.1 cal = 4.186 J.

Every now and then it is tricky to accurately measure the amount of heat that is produced by a substance. The measurement is made easier by burning a particular quantity of the fuel to heat up water. The energy expelled by the fuel can then be estimated by calculating the heat absorbed by the water as calculated by the change in temperature of the water. Heat gained by water can be denoted by

Q = change T * m * c

whereT is the temperature change, m is the mass, and c is the specific heat capacity constant of water.

A brief summary of energy flow through the body

Food that we ingest contains energy. The maximum amount of energy contained in the food we eat is a measure of the heat that is released after a total combustion of the food to carbon dioxide (CO2) and water in a bomb calorimeter. This energy is termed ingested energy (IE) or gross energy (GE).

STATE OF MATTER

from Femosky110 on 06/12/2020 01:15 PM

STATE OF MATTER
Matter in the solid state has a definite volume and shape, with essential particles within the matter -atoms, molecules or ions very close together and fixed into definite position. Matter in the liquid state has a definite volume, with a changeable shape. It easily settles in to fit the shape of its container. Its particles are still close together but move about freely. Matter in the gaseous state does not have a definite shape or volume. It has both variable volume and shape, and adapts to fit its container. Its particles are not close together. They are as well not fixed in place. Matter in the plasma state exhibits variable volume and shape, but like neutral atoms, it possesses a considerable number of ions and electrons, both of which can travel around freely. Plasma is the most widespread form of observable matter in the world.

 

Kinetic Theory of Matter
The Kinetic Theory of Matter states that matter is made up of a large number of small particles - individual atoms or molecules that are in continuous motion. This theory is as well known as the Kinetic Molecular Theory of Matter and the Kinetic Theory.

By making a number of simple assumptions, like the idea that matter is made of extensively spaced particles in constant motion, the theory tries to give explanation to the behavior of matter. Two significant areas elucidated are the gush or transmission of heat and the association between pressure, temperature, and volume properties of gases.

Possible Questions you may be asked:

• What are the assumptions of the kinetic theory of matter?

• How does the theory explain heat flow?

• How does the kinetic theory of matter explain pressure and volume?

Assumptions of kinetic theory
The Kinetic Theory of Matter is a guess of how matter ought to behave, based on definite assumptions and estimations. The assumptions are derived from observations and experiments, like the fact that materials consist of small molecules or atoms. Approximations are made to keep the theory from being too complex. One assumption is that the size of the particles is so small that it can be considered a point.

Matter consists of small particles

The number 1 assumption of this theory is that matter consists of a huge number of very small particles that could either be individual atoms or molecules.

Large separation between particles
The second assumption of the theory deals with the disconnection of the particles.

• In a gas, the distance between particles is very large compared to their size, to such extent that there are no attractive or repulsive forces between the molecules of a gas.

• In a liquid, although the particles are still far apart, they are close enough to allow attractive forces lock up the materials to the shape of its container.

• In a solid, the particles are very closely knit together that the forces of attraction shut in the material to a definite shape.

Particles in continuous motion
The third assumption is that all the particles are in continuous motion.

In gases, the motion of the particles is assumed to be haphazard and free. In liquids, the motion is fairly inhibited by the volume of the liquid. In solids, the motion of the particles is strictly confined to a small space, in order for the solid to maintain its shape.

The velocity of each particle determines its kinetic energy.

Collisions transfer energy
The numerous particles often collide with each other. Also, if a gas or liquid is confined in a container, the particles collide with the particles that make up the walls of a container.

Approximations
When atoms or molecules collide, energy may be given off in the form of electromagnetic radiation. Taking this into account could make the theory highly complex, and since the amount of radiation is small in most situations, an approximation is made that this effect is negligible.

Also, atoms and molecules have a discrete size. But charting the collisions of such particles would again make the theory too complex. Thus an approximation is made to say the size of the particles is a simple point, especially compared to the distances involved.

No energy change
Thus, an assumption is that the particles transfer energy in a collision with no net energy change. That means the collisions between the particles are perfectly elastic and no energy is gained or lost during the collision. This follows the Law of the Conservation of Energy.

In reality, the collisions are not perfect, and some energy is lost. But for the sake of simplicity in drawing conclusions, this theory makes the collisions elastic.

Thermal energy and heat flow
The motion of a particle determines its kinetic energy, according to the equation

KE = 1/2MV2

where

• KE is the kinetic energy of the particle

• m is its mass

• V2 is the square of its velocity

The total internal kinetic energy of all the particles is called its thermal energy.

The temperature of an object or collection of matter is the average kinetic energy of the particles. Faster particles means a higher temperature. A thermometer is used to measure the temperature and put it into temperature degrees instead of kinetic energy units.

The heat is the transfer of thermal energy from an object of higher temperature to one of lower temperature. For example, an object feels warm or hot if its temperature is higher than your skin temperature.

The Kinetic Theory of Matter explains heat transfer by conduction, where thermal energy seems to move through a material, warming up cooler areas. This is called heat transfer or heat flow

Processes not covered in this theory are heat transfer by convection and by radiation.

chemistry
Collisions transfer energy
The Kinetic Theory of Matter states that the material's particles have greater kinetic energy and are moving faster at higher temperatures. When a fast moving particle collides with a slower moving particle, it transfers some of its energy to the slower moving particle, increasing the speed of that particle.

If that particle then collides with another particle that is moving faster, its speed will be increased even more. But if it hits a slow moving particle, then it will speed up the third particle.

With billions of moving particles colliding into each other, an area of high energy or high heat will slowly diffuse across the material, making other areas warm too. By the Conservation of Energy, the total energy or total heat of the object will remain the same, but the heat will be evenly distributed throughout the object.

Rate of transfer
The rate at which the kinetic or thermal energy is transferred from one particle to another depends on the separation of the particles and their freedom to move.

In a gas, the particles are allowed to move freely, but their separation distance is great, so heat or energy transfer is slow. In a liquid, the heat transfer by conduction is faster because the particles are closer together.

In a solid, the molecules are constrained into a specific location within the material. Although the particles are closer together than in liquids, the constraints in some materials actually prevent the transfer of heat energy. A good example of that is in wood.

Temperature
One important result of the kinetic theory is that the average molecular kinetic energy is proportional to the absolute temperature of the material. Absolute temperature is measured in the Kelvin scale. But in general, you can say that temperature is the measurement of the average internal kinetic energy of the material or object.

Pressure, volume and temperature
If a gas is enclosed in a container, it exerts pressure on the walls of the container. The Kinetic Theory of Matter explains gas pressure as the total force exerted by gas molecules colliding against the walls of a container.

If the container can expand, like with a balloon or cylinder and piston, increasing the pressure can increase the volume. Like, the balloon will get bigger. Also, if you increase the temperature of the gas--and thus the kinetic energy of its molecules—you increase the pressure or the volume of the container.

This leads to a relationship between pressure, volume and temperature in an ideal gas. (An ideal gas is a gas that follows the assumptions of the Kinetic Theory of Matter.) The relationship is

PV = NkT

where:

• P is the pressure of the ideal gas

• V is the volume of the gas container

• N is the number of gas particles

• k is the Boltzman constant in joule per kelvin per particle

• T is the temperature in the absolute or kelvin scale

This equation has a number of implications, including:

• If you decrease the pressure and hold the volume constant, the temperature decreases (principle of a refrigerator)

• If you increase the temperature and hold the pressure constant, the volume increases (heating a balloon)

• Kinetic Molecular Theory of Matter

• I. Kinetic Theory of Matter is theory that explains the effects of temperature and pressure on matter

A. 3 Postulates

1. All matter is made up of tiny particles.

2. These particles are in constant motion.

3. Collisions between these particles are perfectly elastic.

• B. Four States of Matter

1. Solid

2. Liquid

3. Gas

4. Plasma

• II. Gases

A. Distinguishing Properties of Gases

1. Gases have no definite shape and no definite volume. They take the shape of their container.

2. Particles move very rapidly in gases.

3. Gases have lower densities thatn solids or liquids because the particles are not as close together.

4. Gases can be compressed because there is alot of space between the particles.

5. They expand when heated.

• B. Gas Pressure

1. A gas exerts a pressure on its container because the gas molecules are constantly colliding with the walls of the container. Each collision exerts a force on the walls of the container.

2. Atmospheric pressure is the pressure that the gases in our atmosphere exert on everything on earth.

Atmospheric pressure is equal to:

a. 101.325 kPa

b. 1 atm

c. 760 mm Hg

d. 760 torr

e. 760 millibars

f. 14.7 lbs/in2

3. Manometer - an instrument used to measure gas pressure.

There are two kinds of manometers:

a. open arm manometer

b. closed arm manometer (also known as a barometer)

C. Motion and Physical States

1. Temperature - a measure of the average kinetic energy of the particles in a substance.

2. Kinetic Energy - energy an object posses because of its motion. KE = 1/2 mv2 where m = mass and v = velocity

3. absolute zero - the temperature at which all molecular motion stops. Absolute Zero = -273 oC or 0 K

4. Converting from Celsius to Kelvin

• K = oC + 273

• 5. Energy always flows from an object of higher temperature to one of lower temperature until they both reach the same temperature.
6. Heat is the amount of energy transferred from a warmer object to a cooler object. Heat is measured in Joules.

• III. Distinguishing Properties of Liquids

A. Liquids have definite volume and definite shape.

B. Particles slide past one another.

C. Generally liquids are less dense than solids. (Solid water and Liquid water are exceptions)

D. Liquids are less compressible than gases.

E. Liquids are viscous.

1. Viscosity is the internal friction of a liquid. We also say that it is the liquid's resistance to flow.

2. High Molecular Weight - High Viscosity

3. Low Molecular Weight - Low Viscosity

• F. Surface Tension - contractive force along the surface of a liquid.

Example: This is why some insects can walk on water.

Example: Soap decreases surface tension.

G. Vapor Pressure - pressure exerted by the molecules of a confined vapor

H. Heat (Enthapy) of Vaporization: total heat or energy required to evaporate a liquid.

I. Normal Boiling Point: the temperature at which the vapor pressure is equal to the standard atmospheric pressure (101.325 kPa).

J. Difference between Boiling and Evaporation:

1. Evaporation: entirely a suface effect that can occur at any temperature (liquid to gas)

2. Boiling: bubbles form at the bottom of a liquid and rise to the top. (liquid to gas) It can only take place at certain temperatures and pressures.

K. Hydrogen Bonding in Water

1. Compounds containing hydrogen bonded to N, O, or F are very polar and form hydrogen bonds.

Hydrogen Bonds are not as strong as an actual chemical bond but it can hold the two molecules firmly together.

2. Ice is less dense than liquid water. This is because water expands when it freezes into ice. This occurs because hydrogen bonding pulls the molecule into an open crytalline structure that occupies more space than the liquid.

• IV. Distinguishing Properties of Solids

A. Solids have definite volume and definite shape.

B. Particles have little movement, but they do vibrate against one another.

C. Pure solids melt at definite temperatures.

D. When solids melt, a definte amount of heat is absorbed.

E. Melting Point: temperature at which a solid turns into a liquid.

F. Heat (Enthalpy) of Fusion: total heat or energy required to melt a substance.

G. All solids are made of crystals. Crystals have repeating, 3-D patterns.

H. Solids can form allotropes. Allotropes are two or more different molecular forms of the same elements.

Three Basic Assumptions of the Kinetic Theory?
Kinetic energy is the energy produced or exerted by an object in motion. This makes 3 basic assumptions. There is matter (the object exists), it is moving (in motion), and it is producing or exerting energy.

Gases : Graham's Laws of Diffusion and Effusion

• Only a few physical properties of gases depends on the identity of the gas.

• Diffusion - The rate at which two gases mix.

• Effusion - The rate at which a gas escapes through a pinhole into a vacuum.

Thomas Graham
Graham's Law of Diffusion

The rate at which gases diffuse is inversely proportional to the square root of their densities.

Since volumes of different gases contain the same number of particles (see Avogadro's Hypothesis), the number of moles per liter at a given T and P is constant. Therefore, the density of a gas is directly proportional to its molar mass (MM).

Graham's Law of Effusion
The rate of effusion of a gas is inversely proportional to the square root of either the density or the molar mass of the gas.

The time required for 25-mL samples of different gasses to diffuse through a pinhole into a vacuum.

The Kinetic Molecular Theory and Graham's Law

Since KEavg is dependent only upon T, two different gases at the same temperature must have the same KEavg

Simplify the equation by multiplying both sides by two:

Rearrange to give the following:

Take the square root of both sides to obtain the following relationship between the ratio of the velocities of the gases and the square root of the ratio of their molar masses:

This equation states that the velocity (rate) at which gas molecules move is inversely proportional to the square root of their molar masses.

Diffusion
Diffusion refers to the process by which molecules intermingle as a result of their kinetic energy of random motion. Consider two containers of gas A and B separated by a partition. The molecules of both gases are in constant motion and make numerous collisions with the partition. If the partition is removed as in the lower illustration, the gases will mix because of the random velocities of their molecules. In time a uniform mixture of A and B molecules will be produced in the container.

The tendency toward diffusion is very strong even at room temperature because of the high molecular velocities associated with thethermal energy of the particles.

STOICHIOMETRY

from Femosky110 on 06/12/2020 01:09 PM

STOICHIOMETRY AND CHEMICAL REACTIONS
Stoichiometry is a branch of chemistry that is concerned with the relative quantities of reactants and products in chemical reactions. In a balanced chemical reaction, the relationship among quantities of reactants and products characteristically form a ratio of positive numerals. For instance, in a chemical reaction that forms ammonia (NH3), precisely 1 molecule of nitrogen gas (N2 ) reacts with 3 molecules of hydrogen gas (H2) to generate 2 molecules of NH3 . See below:

 

N

2 + 3H

2 → 2NH

3

This type of stoichiometry which describes the quantitative relationships between substances when they take part in chemical reactions is referred to as reaction stoichiometry. In the above sample reaction, reaction stoichiometry explains the 1:3:2 molecular rations of nitrogen, hydrogen, and ammonia.

Stoichiometry can be employed to estimate quantities like the amount of products in mass, moles and volume that can be produced with given reactants and percentage yield. This means the percentage of the particular reactant that is converted into the product. Stoichiometry extimations can guess the way elements and components diluted in a standard solution react in experimental conditions.

Stoichiometry is founded on the law of conservation of mass which states that the mass of all the reactants in a chemical reaction is equivalent to the mass of the products.

Composition stoichiometry explains the quantitative (mass) relationships between elements that make up a compound. For instance, composition stoichiometry explains the nitrogen to hydrogen ratio in the compound ammonia (NH3): 1 mol of ammonia is composed of 1 mol of nitrogen and 3 mol of hydrogen. As the nitrogen atom is roughly 14 times heavier than the hydrogen atom, the mass ratio is 14:3; consequently 17 kg of ammonia is composed of 14 kg of nitrogen and 3 kg of hydrogen.

A stoichiometric amount or stoichiometric ratio of a reagent is the most favorable amount or ratio at which the reaction proceeds to completion and in which

1. Every one of the reagent is used up

2. There is no shortage of the reagent

3. There is no surplus of the reagent.

A non-stoichiometric mixture, which the chemical reaction has reached the completion, is liable to have only the restrictive reagent consumed completely.

Although nearly all chemical reactions possesses integer-ratio stoichiometry in amount of matter units -moles, number of particles, a few non stoichiometric compounds that cannot be shown ratios of distinct intergers are available. These substances, consequently, go against the law of definite proportions that forms the foundation of stoichiometry together with the law of multiple proportions.

Gas stoichiometry deals with reactions involving gases, where the gases are at a known temperature, pressure, and volume, and can be assumed to be ideal gases. For gases, the volume ratio is ideally the same by the ideal gas law, but the mass ratio of a single reaction has to be calculated from the molecular masses of the reactants and products. In practice, due to the existence of isotopes, molar masses are used instead when calculating the mass ratio.

Laws of chemical combination
It was an Englishman of the 17th century known as Robert Boyle who after his research and findings on the behaviour of gases, made available an unambiguous evidence for the atomic composition of matter. He was the foremost to describe an element as a material that cannot be chemically broken down into a simper form. He was of the opinion that a number of dissimilar elements might exist in nature.

Laws of chemical combination
The fundamental laws of chemical combination are:

• The law of conservation of mass

• The law of constant composition, and

• The law of multiple proportions.

The law of conservation of mass
This law states that the mass of a closed system will stay constant over time, in spite of the processes acting within the system. A comparable statement is that mass cannot be created/destroyed, despite the fact that it can change into one form or the other. This means for any chemical process in a stopped up system, the mass of the reactants must be the same with the mass of the products.

Law of constant composition
The law of constant composition states that the composition of a particular substance is always the same, in spite of the way the substance was made or wherever the substance exists. If take water for instance, it is known that a molecule of water always consist of 2 atoms of hydrogen and 1 atom of oxygen. Whenever the composition of a molecule alters, the result will no longer be the same substance but a different one possessing different properties.

The law of multiple proportions
The law of multiple proportions states that when elements combine to form compounds they do so in a ratio of minute whole numbers. For instance carbon and oxygen react to form CO or CO2, but not in fractions like CO1.2. In addition, the law states that if two elements form more than one compound between them; then the ratios of the masses of the second element united with a fixed mass of the foremost element will as well exist in ratios of small non-fractional integers.

Types of Chemical Equations
A chemical equation is composed of chemical formulas of the reactants -the reacting substances and the chemical formula of the products- the substances created during the chemical reaction. The two are alienated by an arrow symbol which is normally read as "yields" and every individual substance's chemical formula is alienated from the rest by a plus sign.

For an example, the equation for the reaction of hydrochloric acid with sodium can be shown as:

2 HCl + 2 Na → 2 NaCl + H2

It is highly crucial for a chemist to be capable of writing accurate balanced equations and to interpret equations written by others. It is also extremely useful for him or her to be aware of the way to foretell the products of some specific types of reactions.

A Chemical Equation shows:

1. The reactants which combine together in the reaction.

2. The products which are created by the reaction.

3. The amounts of every substance used and every substance formed.

Two significant principles to bear in mind when writing a chemical equation:

1. Every chemical compound has a formula which cannot be changed.

2. A chemical equation gives account of all the atoms used in the chemical reaction. This is an application of the Law of Conservation of Matter. It states that in a chemical reaction atoms are neither created nor destroyed.

C. A few things to bear in mind about writing equations:

1. The diatomic elements when they stand alone are always written as H2, N2, O2, F2, Cl2, Br2 and I2

2. The sign, →, is used to denote "yields" and illustrates the direction of the action.

3. A minute delta, ( ), on top of the arrow illustrates that heat has been supplied.

4. A double arrow, ↔, illustrates that the reaction is reversible and can move in both directions.

5. Before starting to balance an equation, crosscheck every one of formulas to ensure that they are right. You must never alter a formula all through the balancing of an equation.

6. Balancing of an equation is done by putting coefficients in front of the formulas to make sure you have got equivalent number of atoms of everyone of the element on the two sides of the arrow.

Four basic types of chemical reactions
A. Synthesis or composition reaction:

• In this type of reaction, two or more elements or compounds may mingle to form a more complex compound.

The basic formula for this type of reaction is : A + X → AX

Some instances of synthesis reactions are:

1. Metal + oxygen → metal oxide

EX. 2Mg(s) + O2 (g) → 2MgO(s)

2. Non-metal + oxygen → nonmetallic oxide

EX. C(s) + O2(g) → CO2(g)

3. Metal oxide + water → metallic hydroxide

EX. MgO(s) + H2O(l) → Mg(OH)2(s)

4. Non-metallic oxide + water → acid

EX. CO2(g) + H2O(l) → ; H2CO3(aq)

5. Metal + non-metal → salt

EX. 2 Na(s) + Cl2(g) → 2NaCl(s)

6. A few nonmetals combine with each other.

EX. 2P(s) + 3Cl2(g) → 2PCl3(g)

You ought to know these two reactions and try to remember them:

N2(g) + 3H2(g) → 2NH2(g)

1. NH3(g) + H2O(l) → NH4OH(aq)
B. Decomposition reaction:

• In a decomposition reaction, one compound breaks down into its component parts or simpler compounds.

Basic equation formula for this type of reaction is AX → A + X

Some instances of decomposition reactions are

1. Metallic carbonates, when heated, form metallic oxides and CO2(g).

EX. CaCO3(s) → CaO(s) + CO2(g)

2. The majority metallic hydroxides, when heated, decompose to form metallic oxides and water.

EX. Ca(OH)2(s) → CaO(s) + H2O(g)

3. Metallic chlorates, when heated, decompose to form metallic chlorides and oxygen.

EX. 2KClO3(s) → 2KCl(s) + 3O2(g)

4. Some acids, when heated, decompose to form non metallic oxides and water.

EX. H2SO4 → H2O (l) + SO3(g)

C. Replacement reaction:

• A more reactive element takes the place of another element in a compound and frees the less active one.

• Basic form: A + BX → AX + B or AX + Y → AY + X

Examples of replacement reactions
1. Replacement of a metal in a compound by a more active metal.

EX. Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)

2. Replacement of hydrogen in water by an active metal.

EX. 2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)

EX. Mg(s) + H2O(g) → MgO(s) + H2(g)

3. Replacement of hydrogen in acids by active metals.

EX. Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)

4. Replacement of nonmetals by more active nonmetals.

EX. Cl2(g) + 2NaBr(aq) → 2NaCl(aq) + Br2(l)

D. Ionic:

• This takes place among ions in aqueous solution. The reaction will take place when one pair of ions approach together to create at least one among the following:

1. a precipitate

2. a gas

3. Water or a number of other non-ionized substances.

Basic form of the equation: AX + BY → AY + BX

Some examples of ionic reactions:

1. Formation of precipitate.

EX. NaCl (aq) + AgNO3(aq) → NaNO3(aq) + AgCl(s)

EX. BaCl2(aq) + Na2SO4(aq) → 2NaCl(aq) + BaSO4(s)

2. Formation of a gas.

EX. HCl(aq) + FeS(s) → FeCl2(aq) + H2S(g)

3. Formation of water. When a reaction takes place between an acid and a base, the reaction is known as a neutralization reaction.)

EX. HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

EMPIRICAL AND MOLECULAR FORMULAE
The empirical formula of a compound is the simplest formula of that compound. A molecular formula is the equivalent to or is a multiplication of the empirical formula, and is focused on the definite number of atoms of every type in the compound. For instance, if the empirical formula of a compound is C3H8, its molecular formula might be be C3H8 , C6H16 and so on .

CHEMICAL BONDING

from Femosky110 on 06/12/2020 01:08 PM

Chemical Bonding
There are numerous types of chemical bonds and forces acting jointly to combine molecules together. The two most fundamental types of bonds are ionic and covalent bond. In ionic bonding, atoms transfer electrons to each other. Ionic bonds need at least one electron donor and one electron acceptor. On the contrary, atoms that have similar electro negativity share electrons through covalent bonds as for such atoms, donating or receiving electrons are not favorable.

 

Chemical bonding is a means through which atoms unite to form molecules. Chemical bond exists between two atoms or groups of atoms when the forces acting between them are physically powerful enough to result to the formation of an aggregate with adequate stability to be termed an autonomous species. The no of bonds an atom forms matches up to the number of electron at its outer shell. Bond energy is the quantity of energy necessary to break a bond and create neutral atoms. In line with Coulomb's law every bond as a result of attraction that exist between unlike charges. On the other hand, the manner this force is manifested varies depending on the atoms concerned. The main types of chemical bond are the ionic, covalent, metallic, and hydrogen bonds. The ionic and covalent bonds are ideal forms but the majority of the bond types are of an intermediary type.

Bonding energy between two atoms
The interaction energy between two atoms at equilibrium is referred to as the bonding energy between the two atoms. To break the bond, this energy must be supplied from outside. Breaking the bond means that the two atoms become infinitely separated. In real substances that are made up of varieties of atoms, bonding is calculated by stating the bonding energy of the entire substances in terms of the disjointing distances among all atoms. There are different types of bonding:

• Primary bonding: Ionic (involves transfer of outermost electrons)

• Covalent (involves sharing of outermost electrons, directional)

• Metallic (involves delocalization of valence electrons)

• Secondary or van der Waals Bonding:(widespread, but less strong than primary bonding)

• Dipole-dipole

• H-bonds

• Polar molecule-induced dipole

• Variable dipole (the most weak bond)

The Ionic Bonding
Ionic bonding is the total transfer of outermost electron(s) between atoms. It is the type of chemical bond that produces two oppositely charged ions. In ionic bonds, the metal loses electrons to turn into a positively charged cation, while the non-metal receives those electrons to turn into a negatively charged anion. For ionic bond to occur there must be an electron donor, metal, and an electron acceptor, non metal.

Ionic Bonding is occurs because metals have a small number of electrons in their outmost orbital. Through the loss of those electrons, these metals can attain noble-gas configuration and meet the octet rule. Likewise, non metals that have nearly 8 electrons in their outermost shell have the tendency of readily accepting electrons to attain their noble gas configuration. In ionic bonding, over 1 electron can be donated or received to fulfill the octet rule. The charge on the anion and cation matches up with the number of electrons contributed or received. In ionic bonds, the net charge of the compound must be zero.

The ionic bond is a chemical bond formed as a result of attraction between two opposite charged ions. The atoms of metallic elements like sodium easily lose their valence electrons, whereas the atoms of non-metals like chlorine have the tendency to gain electrons. The reaction between them results to a highly stable ions which maintain their individual structures while approaching one another to form a stable molecule or crystal. In an ionic crystals such as sodium chloride, no separate diatomic molecules are present; instead, the crystal is made up of composed of independent Na+ and Cl− ions, with each being attracted to adjoining ions of the opposite charge giving rise to one single gigantic molecule.

chemistry
The covalent bond
The covalent bond is the type of bond formed when two atoms share a pair of electrons. There is no net charge on each of the atoms; the attractive force between them is formed through the interaction of the pair of electron within the nuclei of both atoms. When the interacting atoms share more than two electrons, it leads to the creation of double and triple bonds. This is because every shared pair forms its own particular bond. The interacting atoms, by sharing their electrons are able to attain a highly stable electron configuration that correspond to that an inert gas.

Covalent Bonding
Covalent bonding is the chemical bond that results from sharing of electrons between atoms. This type of bonding arises between two atoms of the identical element or elements that are placed close to each other in the periodic table. Covalent bonding occurs mainly between non metals; but it can as well be found between non metals and metals alike.

Polar and non-polar physical properties of covalent compounds

Physical properties Covalent compounds
States (at room temperature) Solid, liquid, gas
Electrical conductivity Usually none
Electrical conductivity Usually none
Boiling point and Melting Varies, but usually lower than ionic compounds
Solubility in water Varies, but usually lower than ionic compounds
If we take methane (CH4), as an example; in methane, carbon shares one electron pair with each of the 4 hydrogen atom; so that the total number of electrons shared by carbon is eight, which matches up with the numbers of electron in the valence shell of neon; every hydrogen atom shares two electrons, which matches up with the electron configuration of helium.

In the majority of covalent bonds, every one of the atom contribute just a single electron to the shared pair. In some instances however, the two electrons are donated from the same atom. When this happens, it gives rise to a partially ionic character giving rise to what is called a coordinate link. In actual fact, a purely covalent bond can only be found among two identical atoms.

Covalent bonds play a significant role in organic chemistry due to the capability of the carbon atom to form 4 covalent bonds. These bonds are arranged in specific directions in space, resulting to the complex geometry of organic molecules. If every one of the four bonds is one just like in methane, the resulting molecule will have the shape of a tetrahedron. The significance of shared electron pairs was originally discovered by the

American chemist G. N. Lewis (1916), who stated that there are only extremely few stable molecules that exist which have a total numbers of electrons that is odd. His octet rule permits chemists to forecast the most likely bond structure and charge allocation for molecules and ions. With the initiation of quantum mechanics, it was recognized that the electrons in a shared pair must possess opposite spin, as required by the Pauli Exclusion Principle.

The molecular orbital theory
The molecular orbital theory was developed to foretell the accurate sharing of the electron density in a variety of molecular structures. The American chemist Linus Pauling initiated the concept of resonance to clarify how stability is achieved when above one practical molecular structure is achievable: the actual molecule is a coherent mixture of the two structures.

Metallic and hydrogen bond
Contrary to ionic and covalent bonds, which are copiously available in a great number of molecules, the metallic and hydrogen bonds are highly specific.

The metallic bond is the bond accountable for the crystalline structure of pure metals. This bond cannot be ionic due to the fact that every one of its atoms is identical. It cannot also be covalent ordinarily due to the fact that there are very few valence pairs of electrons to be shared among adjoining atoms. As an alternative, the valence electrons are shared jointly by all the atoms in the crystal. The electrons act as a free gas moving within the lattice of preset, positive ionic cores. The intense mobility of the electrons in a metal gives explanations for its high thermal and electrical conductivity.

Hydrogen bonding is a very powerful electrostatic attraction between two independent polar molecules. That is between the molecules in which the charges are unequally dispersed, characteristically containing nitrogen, oxygen, or fluorine. These elements have physically powerful electron-attracting power, and the hydrogen atom serves as an overpass between them. The hydrogen bond, which plays a crucial role in molecular biology, is by far weaker than the ionic or covalent bonds. Hydrogen bond is answerable for the structure of ice.

Bonding in Organic Chemistry
Ionic and Covalent bonds are the two top limits of bonding. Polar covalent is the midway type of bonding in between the two extremes. Some ionic bonds possess covalent character and some covalent bonds are partly ionic. For instance, the majority of carbon-based compounds are covalently bonded, however they can also be partly ionic.

Polarity is an evaluation of the separation of charge in a compound. A compound's polarity is reliant on the symmetry of the compound together with the differences in electronegativity between atoms. Polarity arises when the electron pushing elements from the left side of the periodic table, shares electrons with the electron-pulling-elements from the right side of the period table. This generates a spectrum of polarity, with ionic (polar) at one end, covalent (non-polar) at the other end, and polar covalent in the center.

In co-operation, these bonds are vital in Organic Chemistry. Ionic bonds are significant because they allow the synthesis of specific organic compounds. Covalent bonds are particularly essential since most carbon molecules interact primarily through covalent bonding. Covalent bonding permits molecules to share electrons with other molecules, forming long chains of compounds and giving rise to more complexity in life.

chemistry
Polar and Non-Polar Shapes
Molecules that have a linear, trigonal planar, tetrahedral, trigonal bipyramidal, or octahedral shape, are non-polar in nature. These are shapes which do not have non-bonding lone pairs like Methane, CH4. However if a few bonds are polar while the rest are not, there will be a general dipole, and the molecule will be polar. Example Chloroform, CHCl3.

Dipole-Dipole Bonds
When two polar molecules come close to each other, they will position themselves in order to let the negative and positive sides' line up. There will be an attractive force linking the two molecules together, but it is not virtually as well-built a force as the intramolecular bonds. This explains the way different types of molecules bond together to form bulky solids or liquids.

Van der Waals forces are initiated by temporary dipoles formed when electron locations are asymmetrical. The electrons are continually tracking the nucleus, and by chance they could come very close together. The uneven concentration of electrons could result to one side of the atom becoming more negatively-charged than the other, forming a temporary dipole. Van der Waals forces are the reason why nitrogen can be liquified.

PERIODICITY CHEMISTRY

from Femosky110 on 06/12/2020 01:06 PM

PERIODIC CHEMISTRY
The periodic table is a table showing the elements prearranged in order of increasing atomic number, in accordance with the periodic law. In the periodic table, elements that have related chemical properties and electronic structures are placed in vertical columns known as the groups.

 

Periodicity of the elements
Periodicity is one among the basic aspects of the elements in the periodic table.

What Is Periodicity?
Periodicity of elements means the persistent trends that are visible in the properties of element. These trends that exist in the property of elements became noticeable to Mendeleev when he prearranged the elements in the periodic table order of increasing mass. From the properties that were displayed by the recognized elements, it was easy for Mendeleev to foretell where there were "breaks" in his table, or elements that were not yet discovered.

The contemporary periodic table is extremely related to Mendeleev's table, but in the present day elements are prearranged in the order of increasing atomic number, which showcases the number of protons in an atom. There are no unidentified elements; even though fresh elements can be formed which have even larger numbers of protons.

The Periodic Properties are enumerated below:
1. Ionization energy – Ionization energy is energy needed to remove an electron from an ion or gaseous atom.

2. Atomic radius – Atomic radius is the distance between the centers of two atoms that are in close relationship with each other.

3. Electronegativity – This is a measure of the ability of an atom to form a chemical bond

4. Electron affinity –This is an ability of an atom to accept an electron

Periodic Trends or Periodicity
The periodicity of the above properties follows trends as you go across a row or period on the periodic table or down a column or group on the periodic table.

While moving from Left to Right-across the period

• Ionization Energy Increases

• Electronegativity Increases

• Atomic Radius Decreases

While moving Top to Bottom-down the group

• Ionization Energy Decreases

• Electronegativity Decreases

• Atomic Radius Increases

The definition of the Periodic Law
The Periodic Law states that the physical and chemical properties of elements in the periodic table reappear in a methodical and conventional way when the elements are prearranged in order of increasing atomic number.

chemistry
The elements of the first transition series
Even though the transition elements have a lot of broad chemical similarities, every one of them has a thorough chemistry of its own. The adjoining relationships are typically found amongst the three elements in every vertical group of the periodic table, even though inside every group, the element of the first series typically varies more from the rest two than they vary from each other. The majority of the first series elements are more recognizable and theoretically significant than the heavier members of their vertical group.

A small number of the chemical trends among the elements of the first transition series may be capsulated.

1. Titanium to manganese exhibits the highest oxidation state, which is normally found among oxo compounds, fluorides, or chlorides and corresponds to the total number of 3d and 4s electrons in the atom. The stability of this uppermost oxidation state decreases from titanium in the +4 state to manganese in the +7 state. Next to manganese—ie among iron, cobalt, and nickel, oxidation states related to the loss of all 3d and 4s electrons do not take place; higher oxidation states generally turn out to be increasingly more complicated to reach because the growing nuclear charge makes the 3d electrons to be additionally securely bound. It is only the following elements that exhibits very high oxidation states - chromium (+5, +6 states), manganese (+5, +6, +7 states), and iron (+5, +6 states) and with the exception of fluorides, such as chromium pentafluoride, CrF5 (where the chromium is in the +5 state), and chromium hexafluoride, CrF6 (where chromium is in the +6 state), and oxofluorides like manganese trioxide fluoride, MnO3F (occur with manganese in the +7 state), the most important chemistry in these variable oxidation states is that of oxo anions such as permanganate, MnO4− (+7 state); chromate, CrO42− (+6 state); and ferrate, FeO42−(+6 state). Every one of these compounds is very good oxidizing agent.

2. The oxides of the entire element become more acidic as the oxidation number increases, and the halides become more covalent and able to easily undergo hydrolysis.

3
. In the oxo anions that are mostly found in the higher oxidation states, the metal atom is tetrahedrally bordered by oxygen atoms, while in the oxides created in the lower oxidation states, the atoms are typically octahedrally synchronized.

4. In the oxidation states of +2 and +3, complexes in aqueous solution or in crystals is typically four, five or six step.

5. Oxidation states less than +2 are not regularly found in the chemistries of the transition elements, apart for copper although it could be found in all the elements through the use of ligands like that of carbon monoxide.

The group 7 elements (The halogens)
Elements of group 7 are as well known as the halogens. They consist of fluorine, chlorine, bromine and iodine. All of them have seven valence electrons in their outside shell.

In a displacement reaction, a less reactive element is displaced by a more reactive element.

The group 7 elements are put in the vertical column second from right in the periodic table.

Chlorine, bromine and iodine are the three Group 7 elements that are mostly available in the secondary school. Fluorine is excessively reactive and cannot easily be produced and preserved in the school. Reaction of Group 1 elements reacts with group 7 element to form salt and because these, they are known as ('salt formers').

Properties and uses of the halogens
The table summarizes some of the properties and uses of three halogens.

Group 7 element Properties Typical use
Chlorine Green gas Sterilising water

Bromine Orange liquid Making pesticides and plastics

Iodine Grey solid Sterilising wounds

Iodine forms a purple vapour when it is warmed.

Group 7 properties
The halogens are diatomic which means that they exist as molecules, each with one pair of atoms. The formulas for their molecules are written as Cl2, bromine Br2 and iodine I2.

Physical properties of halogens
The halogens show trends in their physical properties down the group.

Melting point and boiling point
The halogens or elements of group 7 have low melting points and boiling points. This is a characteristic property of non-metals. Fluorine has the smallest melting point and boiling point. The melting points and boiling points of halogens starting form flouring increases down the group.

Melting and boiling points of Group 7 elements
State of the halogens at room temperature

25°C is normally considered as the room temperature. At this particular temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine and astatine are solids. There is for that reason a trend in state from gas to liquid to solid as you move down the group.

The Colour of the halogen
The halogens happen to be darker as you move down the group. Fluorine is extremely pale yellow, chlorine is yellow-green, and bromine is red-brown. Iodine crystals are glossy purple - but they when they are heated up, they easily change into a dark purple vapour.

Predictions
When we can see a trend in the properties of some of the elements in a group, you can likely calculate the properties of other elements in that group. Astatine is placed after iodine in Group 7. The colour of halogens turns darker as you move down the group. Iodine is purple colour, and, as we would imagine, astatine is black-coloured.

The Halogens are commonly non–metals. 'Halogens' means 'salt formers' and the most widespread compound is sodium chloride which can be found naturally in the form of deposits of 'rock salt' or the much more abundantly as the 'sea salt' in the seas and oceans.

The reason Why the melting points and boiling points of Group 7 elements increase with atomic number or down the group

This increase in melting/boiling points down Group 7 is as a result of the increasing weak electrical intermolecular attractive forces that occur with an increase in the size of atom or molecule.

In general, the greater the number of electrons in a molecule, the greater the force of attraction that exist between the molecules.

A table showing the properties of group 7
Symbol and Name Atomic Number Electron arrangement State and colour at room temperature and pressure Melting point Boiling point atom radius pm
F Fluorine 9 2.7 pale yellow gas –219oC, 54K –188oC, 85K 64
Cl Chlorine 17 2.8.7 pale green gas –101oC, 172K –34oC, 239K 99
Br Bromine 35 2.8.18.7 dark red liquid –7oC, 266K 59oC, 332K 114
I Iodine 53 2.8.18.18.7 dark (black) crumbly solid 114oC, 387K 184oC, 457K 133
• The halogens are all poor conductors of heat and electricity – characteristics of non–metals.

• When they are in the solid state, they are brittle and crumbly example. iodine.

• The density increases down Group 7.

• The size of the atom gets bigger down Group 7 as more inner electron shells are filled going down from one period to another.

Chemical features, similarities, and physical property and reactivity trends
1. The atoms all have 7 outer electrons, this outer electron similarity, just like any other Group in the Periodic Table, gives them a very similar chemical properties.

2. They form a single charged negative ions e.g. chloride Cl– because they are one electron less than that of a noble gas electron structure. They only need to gain one negative electron (reduction) to be stable and this gives them a surplus electric charge of –1. These ions formed by the halogens are known as the halide ions, two other halide ions are called the bromide Br–and iodide I– ions.

3. They form ionic compounds with metals e.g. sodium chloride Na+Cl–.

4. The Halogens form covalent compounds with non–metals and with themselves.

5. The bonding in the molecule of halogen compound involves single covalent bonds like the hydrogen chloride HCl or H–Cl.

Important things to note when naming halogen compounds:
When joined with other elements to form simple compounds, the name of the halogen element alters a little from ...ine to ...ide.

Fluorine forms a fluoride (ion F–), chlorine forms a chloride (ion Cl–), bromine a bromide (ion Br–) and iodine an iodide (ion I–).

The other element at the beginning of the compound name like the hydrogen, sodium, potassium, magnesium, calcium, and so on remains unaltered.

So archetypal halogen compounds are named as follows:

• Potassium fluoride, hydrogen chloride, sodium chloride, calcium bromide, magnesium iodide and so on.

The elements of group 7 all exist as diatomic molecules ie X2 or X–X, where X stands for the halogen atom.

A halogen that is more reactive displaces a less reactive one from its salts.

ATOMIC STRUCTURE

from Femosky110 on 06/12/2020 01:05 PM

STRUCTURE OF THE ATOM
Matter is anything that has mass and occupies space. Atoms are fundamental building blocks of matter that cannot be further divided by any chemical means. What are elements?

 

Elements are constituents of matter. There are 92 natural elements. Elements like hydrogen, carbon, nitrogen and oxygen are elements that make up the majority of living things. Other groups of element that exist in living things are: magnesium, calcium, phosphorus, sodium, potassium.

Many elements were discovered before the late 1800's. A Russian scientist Dmitri Mendeleev then proposed an arrangement of elements based on their atomic masses. In the modern time, elements are no longer arranged based on their atomic masses but according to their atomic numbers.

The word atom is a derivative of the Greek word atom which means undividable. The Greeks came to a conclusion that matter could be further divided into particles that are too tiny to be seen with the naked eye. These tiny indivisible particles of matter were referred to as atoms.

An atom is made up of three types of particles:

• Protons

• Neutrons, and

• Electron.

chemistry
The nucleus of an atom is made up of protons and neutrons. The electron of an atom resolves round the nucleus of an atom in an orbit known as shells.

Neutrons are neutral and have no electrical charge while protons and electrons are electrically charged. While Protons are positively charged and have a relative charge of +1, electrons are negatively charged with a relative charge of -1.

The number of protons in the nucleus of an atom is known as its atomic number. Atoms are arranged in atomic number order in the periodic table while electrons are arranged in energy levels or shells. Each energy level holds a definite numbers of electrons.

The electronic structure of an atom is an explanation of the manner the electrons are arranged, which can be demonstrated in a diagram or through numbers. The position of an element in the periodic table and its electronic structure interrelated.

The atomic mass of an element is greatly determined by the number of protons and neutrons in its nucleus. For instance, in a mass number of 150; 149 lbs which equivalent to 15 oz is protons and neutrons while only 1 oz. is the electron's mass. The mass of an electron is extremely small - 9.108 X 10-28 grams.

It is the number of protons in an atom that establishes the atomic number. For example, Hydrogen is with an atomic number of 1.The number of protons in an element is invariable (example, the number of proton in Hydrogen (H) =1 and that of Uranium (Ur) = 92 but the number of neutron may well differ, therefore the mass number (protons + neutrons) of an element could differ.

A particular element may have differing numbers of neutrons; the different forms of an element with the same number of proton but with differing numbers of neutron are referred to as isotopes. Isotopes have the same chemical properties but the physical properties of a number of isotopes might be different.

Some isotopes are radioactive in nature. This means that give out energy while they decompose and break down to a more stable form. This gives rise to another element.

Half-life of a radioactive element is the time that it takes for half of the atoms of that element to decay into stable form. An example of element that exhibits isotopy is oxygen. The element-Oxygen with an atomic number of 8 may possibly have 8 or 9, or 10 neutrons.

chemistry
Atomic Symbols and Isotopes
The atom of every element is composed of electrons, protons and neutrons. Atoms of the same element possess the same number of protons and electrons but the number of neutrons can vary. When the neutrons vary such elements are referred to as isotopes. Due to these isotopes, it got crucial to formulate a notation to differentiate an isotope from the other. This notation is known as the atomic symbol. The atomic symbol is usually denoted with three different letters:

1. The X: This is used to represent the element.

2. The A: This is a symbol that represents the atomic number. This is the number of protons situated on the left side of letter A as a subscript.

3. The Z: This is used to denote the mass no. The mass number is equal to the number of protons and neutrons in the isotope usually placed on top of letter Z as a left superscript.

Relative atomic mass (Ar) of an element is the ratio of the average mass of atoms of that element to 1/12 of the mass of carbon-12 isotope.

IUPAC's definition of Relative atomic mass:
An atomic weight or relative atomic mass of an element is the ratio of the standard mass per atom of the element to 1/12 of the mass of an atom of 12C.

Relative atomic mass scale
The mass of atoms and other tiny particles is calculated on the atomic mass scale as a relative number put side by side the carbon atom. The carbon 12 atom is allocated with the value of exactly 12.0000 on the scale and the whole thing else is calculated with respect to that figure.

Carbon atom Magnesium atom Hydrogen atom
mass = 12 mass = 2 x carbon atom mass = 1/12 x carbon atom
The magnesium atom has double the atomic mass of the carbon atom, so a magnesium atom has a relative mass of 24.

3 helium atoms have atomic mass equivalent to the mass of a carbon atom. This means that each of the 3 helium atoms has a relative atomic mass of 4. The relative atomic mass of an element can either be written as Ar or RAM for short.

Relative molecular mass

Molecules are merely groups of atoms. Therefore they are as well measured on the relative mass scale with carbon 12 just like in relative atomic mass.

Hydrogen atom Oxygen atom water molecule
mass = 1 mass = 16 mass = (2 x 1) + 16 = 18
A water molecule for example has a mass of 3/2 times relative that of a carbon 12 atoms, consequently the relative molecular mass of water is equal to 18.

The relative molecular mass of a substance is obtained by adding up the relative masses of all the atoms that make up a molecule of that substance.

All masses are calculated relative to the mass of a 12C isotope = 12.0000 atomic mass units.

Since relative molecular mass is a comparative calculation, it is not denoted with any unit.

For instance: Benzene has the molecular formula C6H6

A benzene molecule contains 6 carbon atoms and 6 hydrogen atoms.

The relative molecular mass = (6 x relative atomic mass of carbon) + (6 x relative atomic mass of hydrogen)

The relative molecular mass of benzene = (6 x 12) + (6 x 1) = 78

The relative molecular mass of an element can either be written as RMM or Mr for short.

Mole:
The mole is the amount of substance that contains as many "elemental particles - atoms, molecules, ions, electrons as the number of atoms in 12g of carbon-12 isotope.

1 mole of a substance is equal to 6.022 x 1023 items

Subatomic Particles of an atom and their properties

All atoms are composed of three subatomic particles: Protons, neutron and electrons.

The properties of these three sub atomic particles are tabulated below:

Particle Charge Mass (g) Mass (amu)

Proton +1 1.6727 x 10-24 g 1.007316
Neutron 0 1.6750 x 10-24 g 1.008701
Electron -1 9.110 x 10-28 g 0.000549
What we have used in the above table is a unit of mass called the atomic mass unit (amu). This is a better unit to use than grams when discussing masses of atoms. It is defined with the intention that both protons and neutrons have a mass of just about 1 amu. The significant points to remember are bulleted below:

• Protons and neutrons have roughly the same mass, while the electron is more or less 2000 times less heavy.

• Protons and electrons bear charges of equivalent size, but opposite charge. Neutrons have no charge ie they are neutral.

It was at one time believed that protons, neutrons and electrons were spread out in a somewhat uniform fashion to form the atom according to J.J. Thompson's plum pudding model of the atom but in reality the actual arrangement of the atom is rather different.

Electrons move about rapidly just about the nucleus and make up almost the whole volume of the atom. The quantum mechanics are essential to give details of the motion of an electron about the nucleus, but we can say that the sharing of electrons round an atom is in a spherical form.

The force that holds an atom together
The electron which is negatively charged is attracted to the nucleus which is positively charged by a Columbic attraction.

The protons and neutrons are mutually bonded in the nucleus by the strong nuclear force.

The relationship between the structures of an atom with its properties

Chemical reactions occur when there is either a transfer or a sharing of electrons between atoms of same or different elements. What this means is that the chemical properties of an element is for the most part reliant on the number of electrons in one atom of that element. Protons as well play a noteworthy role for the reason that the propensity of an atom to either lose, gain or share electron is reliant on the electrical charge of the nucleus.

Therefore, it is right to conclude that the chemical properties of an atom is reliant on the number of electrons and protons of the atom and the number of neutrons does not add to the chemical properties of that atom.

On the other hand, the mass and radioactive properties of an atom are reliant on the number of protons and neutrons in the nucleus.

chemistry
Atomic Number (Z) -The no of protons

Mass Number (A) - The no of protons] + [the no of neutrons]

The number of protons, neutrons and electrons in an atom are uniquely specified by the following symbol

ASyC, where:

• Sy = The symbol of an element like C, N, Cr) -defines the no of protons

• A = The mass number-[the no of protons] + [the no of neutrons]

• C = The net charge- [the no of protons] – [ the no of electrons]

For instance: A neutral boron 10 atom with 10B

A boron atom according to the periodic table has 5 protons in the nucleus Z = 5.

Since the boron atom is a neutral atom, the number of electrons ought to be equal to the number of protons, 5 electrons.

The mass number of Boron is 10. Therefore, the number of neutrons is A - Z = 10 - 5 = 5 neutrons.

MEET THE BEAUTIFUL VOICE BEHIND MTN's "YOU HAVE ONE MINUTE REMAINING"

from AdminT on 06/12/2020 11:54 AM

There is almost no country on this Earth where the popular network carrier, MTN, is used, that you will not find a very gushing number of people who are really familiar with the alert; "You have one minute remaining". Has anyone ever cared to give it a long thought who the person behind this annoying but nevertheless, BEAUTIFUL voice is? Actually, most people would come to a conclusion that the voice is a computer's. It is not.

Kgomotso Christopher, a South African, an actress and a voice over artist is this culprit.

Beautiful. Isn't she?

Kgomotso Christopher is the voice behind the MTN's Interactive Voice Response system. She is also a Non-Executive Chairperson on the Naledi Theatre Awards Board of Directors. She is a graduate from the University of Cape town with a degree of Bachelor of Arts in Law and Politics and the smart woman was awarded the Jules Kramer Award for Fine Arts when she graduated. In 2004 she earned a Masters of Fine Arts in Theatre Arts at Columbia University in New York City. She continued to live and work in the US and UK until 2008. gomotsoo made guest appearance on television series Madam & Eve, SOS, Backstage, and Moferefere Lenyalong. She has made appearances in theatre productions of Romeo & Juliet, Midsummer Night's Dream, Hamlet and Dr. Faustus. On November 15, 2018 Kgomotso revealed on Instagram that she is the voice behind MTN's Interactive Voice Response system.

A PICTURE OF HER FROM HER HANDLE



SPOILER ALERT:
Kgomotso Christopher is married, so if you think of crushing on her, 

MEET CALVIN CHRISTOPHER







Now that you know who the culprit behind that voice is, tell your friends about it too. 

This is Teach, Learn and Connect!

-AdminT

CONSERVATION OF RESOURCES

from Femosky110 on 06/11/2020 01:57 PM

Ways Of Ensuring Conservation Of Natural Resources
Natural resources are naturally occurring substances that are well thought-out to be valuable in their comparatively natural form. A natural resource's significance relies in the quantity of the substance available and the demand for it.

 

The demand for a natural resource is in turn determined by its efficiency in production. A substance is usually considered a natural resource when the primary activities connected with it are extraction and purification, as opposed to production.

Therefore, mining, petroleum extraction, fishing, hunting, and forestry are normally considered natural-resource industries, while agriculture is not.

Natural resources are majorly classified into renewable and non-renewable resources. Renewable resources are normally living resources like fish, reindeer, coffee, and forests, which can regenerate or renew themselves if they are not over-utilized but used sustainably.

Once renewable resources are eaten at a rate that exceeds their natural rate of replication, the standing stock will reduce and subsequently run out.

The rate of sustainable use of a renewable resource is determined by the substitution rate and amount of standing stock of that particular natural resource. Non-living renewable natural resources are soil and water.

Flow renewable resources are extremely much like renewable resources, only they do not require regeneration, like the renewable resources. Flow renewable resources comprise wind, tides and solar radiation.

Resources can as well be classified on the basis of their basis as biotic and abiotic.

Biotic resources are obtained from living organisms. Abiotic resources are obtained from the non-living things like land, water, and air. Mineral and power resources are as well classified as abiotic resources although a few of them are derived from nature.

Both extraction of the fundamental resource and refining it into a purer, straight usable type like metals and refined oils are usually taken as natural-resource activities, although the refined products may not essentially take place near the extraction point.

A nation's natural resources frequently showcase its wealth and economic strength in the world economy.

Developed nations are nations which are less dependent on natural resources for wealth, as a result of their greater dependence on infrastructural capital for production.

Agencies responsible for conservation of Natural resources
A lot of nations have laws protecting species in danger of extinction. An international treaty, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), was inaugurated in 1975 and it outlawed trade of endangered animals and animal parts.

In the United States, for example, the Endangered Species Act (ESA) was enacted in 1973 to defend endangered or vulnerable species and their habitats.

A fresh scientific field, conservation biology, studies manners to halt the destruction of biodiversity and reinstate natural habitats.

In the United States and Canada, forests are exposed to extensive logging, known as clear-cutting, which destroys plant and animal habitat and leaves the landscape stripped and barren if not appropriately reforested.

A few age-long forests of about 200 to 1,200 years old are still found but are endangered by logging interests. Until the 1990s, the U.S. Forest Service was instructed by Congress to make the most of the harvest of timber in order to supply jobs.

Nevertheless within the late 1980s and early 1990s, environmentalists sued the government for breach the National Environmental Policy Act (NEPA), and intense logging was taken as non sustainable.

Consequently, the timber harvest was minimized and foresters were instructed to abide by a more sustainable policy known as ecosystem management.

This policy necessitated foresters to concentrate on conserving natural habitats instead of capitalizing mostly on tree harvest. In spite of this alteration, many, many very old forests remain unprotected.

b) Conservation Laws
Conservation of natural resources like agriculture, fossil fuels, forestry, waters, and so on is a growing national and international issue, and the complex range of statutes, regulations, and rulings that consist of the body of environmental and natural resources law is in a steady change.

Natural resource lawyers ought not to only have all round knowledge of environmental law, but as well a fundamental perception of the underlying science and the industrial processes in question.

Natural resource attorneys make available a broad array of services.

They may advise clients on land use matters and in the ownership and disposition of natural resources like water, fisheries, timber, minerals, and so on and may stand for clients before the U.S. Forest Service, the U.S. Bureau of Land Management and other resource agencies.

Additionally, they may advise clients in the use of public lands and resources and in the establishment of energy projects with the help of renewable resources.

Since water is one of the most essential resources, a lot of natural resources attorneys assist find the way through complex water rights proceedings and handle the composite wetlands permitting process.

On the wildlife side, a few lawyers assist clients to navigate the complex regulatory requirements connected to the Endangered Species Act, starting from regulatory compliance and counseling, to the expansion of single- and multi-species habitat conservation plans, to the recognition and implementation of multi-forum advances to ESA challenges.

On the court case side, a lot of conservation and land use lawyers have established practices in intricate case and natural resource litigation, trying an extensive variety of cases in state and federal courts.

c) Conservation Education
Conservation Education (CE) assists people of all ages to comprehend and appreciate country's natural resources and study how to conserve those resources for upcoming generations.

Through planned educational experiences and activities embattled to unstable age groups and populations, conservation education allows people to know how natural resources and ecosystems influence each other and how resources can be utilized wisely.

Through conservation education, people widen the decisive thinking skills they require to understand the complexities of ecological problems. Conservation Education as well encourages people to act on their own to conserve natural resources and utilize them in a conscientious manner by making informed resource decisions.

The decline of Earth's biodiversity and the requirement for sustainability practices directs that we require a fresh approach to conservation that conveys to people of every walk of life the essential interdependence of plants, animals, people, and the environment.

This challenge is excessively urgent and very large for any particular organization, government, or discipline to handle alone.

We require practical approaches and fresh partnerships amidst biological and social scientists, government and industry professionals, and citizens to strengthen and protect the intrinsic value of biodiversity, and garner maintenance for sustainable utilization.

CCES studies the multifaceted relationships amongst biodiversity, people, and the environment, and teaches the public about the Earth's biodiversity and how it can be conserved and utilized judiciously.

CCES is committed to enhancing science-related environmental consciousness, biodiversity research and supervising, conservation and the sustainable utilization of Earth's resources.

In modern years, the running down of natural capital and attempts to change to sustainable development has been a main attention of development agencies. This is seen more especially in rainforest regions, which embrace the majority of the Earth's natural biodiversity.

Conservation of natural resources is the main attention of natural capitalism, environmentalism, the ecology movement, and Green Parties. A few see this depletion as a main source of social unrest and conflicts in developing nations.

Some non-renewable resources can be renewable but take an exceptionally long time to refurbish. Fossil fuels, for instance, take millions of years to appear and so are not basically well thought-out as 'renewable'.

Sustainable forest management (SFM) is the administration of forests in relation to the principles of sustainable development. It is as well the current termination in a series of fundamental forest management concepts heralded by sustainable forestry and sustainable yield forestry prior to that.

Sustainable forest management is the expression presently utilized to illustrate approaches to forest management that set extremely broad social, economic and environmental objectives.

A variety of forestry institutions currently practice a range of forms of sustainable forest management and a broad range of methods and tools are accessible that have been tested over time.

Management of Natural Resources
Generally, farmers have pointed to three ways to protect resources by means of traditional technology. They are mechanical, agricultural and vegetative measures.

A) Mechanical Measures
The most important occupation of the hill farmers is agriculture. They regularly construct terraces for cultivation. These terraces are small but there are a lot of them. As a result, it is possible to control rainwater.

Construction of terraces relies on space and grades of land. The farmers, with their expertise, are capable of preparing fields for crop production.

Farmers generate the slopes of the terraces inwards to organize soil erosion and perk up moisture conservation. Soils are made up of gravels and have a high rate of percolation. Due to rainwater retention enough moisture is made accessible to the crops.

On mild slopes farmers create shoulder bunds to protect their lands from soil erosion and plant vegetation over the bunds, especially grasses for fastening the soil.

Irrigation
Farmers used to carry water to their fields through small irrigation channels referred to as gulas. These go from the source of water along the slopes to the fields. In order to avoid seepage losses farmers use pipes.

Management of drinking water
Streams are the source of water in the Himalaya. Farmers give great regard to these water resources. They use the water for drinking and strive to keep streams clean and unpolluted. They sustain vegetation on the banks to have a clean flow without sediment for human consumption.

Water-based industry
In the hills flour mills are not accessible. Farmers have their local technology to run flour mill through water fall. They make use of home-made wooden wheels as turbines to run the mills.

B) Agriculture
Farmers' conventional knowledge of agriculture involves tested technologies in the field. They utilize a particular type of traditional plough. Other forms of 'improved' ploughs do not work in the hills as the soil is made up of gravels and not deep.

Farmers plough their field straight rather than in circles and open parallel furrows for rainwater harvesting and retaining moisture.

Farmers of hill regions have a preference for mixed cropping for reducing the risks under rainfed conditions and generating ground cover for scrutinizing runoff and soil loss. They plant legumes with maize and ginger or turmeric with maize.

Manure And Manuring
In relation to the soil's condition and texture the farmers of the hill region use farmyard manure in the fields prior to sowing. In lowland areas, they as well do green manuring. Although there is increase in the use of artificial manure- fertilisers , farmers retain their belief in traditional methods.

C) Vegetative Measures For Natural Resources Management
Hill farmers plant trees of economic value and suitable to their needs. In order to conserve soil and water they plant grasses for ground cover like Eulaliopsis binnata, Chrysopogun fulvus and agave sps.

Shrubs such as Ipomea icarnea, Arando donex, Dendrocalamus strictus, napier grass, Vitex negundu, Morus alba and bagrera are planted, and in wild form are bhang, lantana, sweet neem, and so on.

There is enormous potential to grow horticulture in the hill ranges due to the undulating topography and climatic conditions.

Farmers are very much aware of the possibility of their lands, but as a result of to poor economic situations and infrastructure it is not probable for them to go ahead with unusual and added profitable land use

NATURAL RESOURCES

from Femosky110 on 06/11/2020 01:56 PM

Conservation Of Natural Resources
Conservation of natural resources refers to the sustainable utilization of natural resources, like soils, water, plants, animals, and minerals, timber, fish, game, topsoil, pastureland, and minerals, and also to the preservation of forests-forestry, wildlife-wildlife refuge, parkland, wilderness, and watershed areas.

 

Conservation of natural resources is currently being embraced in the wider conception of conserving the soil itself by protecting its ability for self-renewal.

For the most part complicated process is the issues that are inherent with nonrenewable resources like oil and coal as well as other minerals of enormous demand.

Present thinking as well favors the protection of the whole ecological regions by the production of "biosphere reserves." Examples of such conservation areas are the Great Barrier Reef off Australia and Adirondack State Park in the United States.

The critical nature of reconciling individual utilization and conservation away from the boundaries of parks has turn into yet another very crucial issue.

The natural resource of an area is made up of its essential capital, and inefficient utilization of those resources leads to an economic loss. From the artistic point of view, conservation as well involves the preservation of national parks, wilderness areas, historic sites, and wildlife.

Natural resources are made up of two major types, renewable natural resources and nonrenewable natural resources.

Examples of renewable natural resources are wildlife and all forms of natural vegetation. The soil itself can be taken as a renewable resource, even though any serious damage to it is not easy to repair due to the sluggish rate of soil-forming processes.

The natural drainage of waters from the watershed of an area can be sustained indefinitely through careful management of vegetation and soils, and the quality of water can be regulated through water pollution control.

Nonrenewable resources on the other hand are those that cannot be replaced or that can be replaced except after an exceptionally long periods of time. Examples of such resources are the fossil fuels like coal, petroleum, and natural gas as well as metallic ores.

Natural Resources: Wildlife and Conservation Biology
The aim of renewable resource conservation is to make certain that resources are not used up faster than they are replaced. Non renewable resources are fossil fuels and mineral deposits, like iron ore and gold ore.

Conservation activities for nonrenewable resources center on maintaining a sufficient supply of these resources far into the future.

Natural resources are conserved for their biological, economic, and recreational values, in addition to their natural beauty and relevance to local cultures.

For instance, tropical rain forests are shielded for their crucial role in both global ecology and the economic livelihood of the local culture; a coral reef may be sheltered for its entertaining significance for scuba divers; and a scenic river may be sheltered for its natural beauty.

Conservation divergences are experienced when natural-resource shortages build up in the face of progressively increasing demands from a growing human population. Disagreement occasionally envelop the way a resource ought to be utilized, or allocated, and for whom.

For instance, a river may provide water for agricultural irrigation, habitat for fish, and water-generated electricity for a factory.

Farmers, fishers, and industry leaders compete for unlimited right of entry into this river, but a freedom like this may obliterate the resource, and conservation methods are essential to safeguard the river for future use.

The competition gets worst when a natural resource extends across political boundaries. For instance, the headwaters, or source of a main river may be situated in a different country than the country through which the river flows.

There is no assurance that the river source will be safeguarded to provide accommodation reserve requirements downstream. Additionally, the manner in which a natural resource is handled has a direct effect upon other natural resources.

Cutting down a forest close to a river, for an example increases erosion, the wearing away of topsoil, and can result to flooding. Eroded soil and silt cloud the river and has adverse affect on a lot of organisms like fish and essential aquatic plants that need clean, clear freshwater to thrive.

Methods of Conservation
The confrontation of conservation is to comprehend the complicated connections among natural resources and reach a sense of balance between resource utilization and protection to make certain a sufficient supply for potential generations.

In order to accomplish this goal, a variety of conservation methods are used. These include reducing consumption of resources; protecting them from contamination or pollution; reusing or recycling resources when probable; and completely defensive, or preserving, resources.

Consumption of natural resources increases considerably every year as the human population increases and standards of living also increases. The large, developed nations, are responsible for the majority of consumption of natural resources due to their high standards of living.

For example, in 1992 an average American used up as much energy as 27 Filipinos or 370 Ethiopians. Conservation education and the considerate utilization of resources are essential in the developed countries to minimize natural-resource consumption.

For instance, minimizing the high demand for tropical hardwoods like teak and mahogany in the United States and Japan would reduce the rate of tropical forest destruction.

To safeguard natural resources from pollution, individuals, industries, and governments have a lot of obligations.

These obligations prevents or limits the utilization of pesticides and other harmful chemicals, limits wastewater and airborne pollutants, averts the production of radioactive materials, and controls drilling and transportation of petroleum products.

Failure to do so leads to contamination in the air, soil, rivers, plants, and animals. For instance, if governments need that all oil tankers be fitted with double-layered hulls, the damages to fisheries and wildlife from the varieties of oil spills of the 20th century, like the 1967 Torrey Canyon oil spill in the English Channel, may have been minimized.

In a lot of instances, it is likely to reuse or recycle resources to lessen waste and resource consumption and conserve the energy desired to manufacture consumer products. For instance, paper, glass, Freon-a refrigerant gas, aluminum, metal scrap, and motor oil can all be recycled.

A preventative measure known as precycling, a general term for designing more robust, recyclable materials like reusable packaging, encourages reuse.

A few resources are very unique or valuable that they are protected from activities that would destroy or degrade them. For instance, national parks and wilderness areas are protected from logging or mining because such activities would reduce the economic, recreational, and aesthetic values of the resource.

Forests and wetlands -areas with high soil moisture or surface water may be protected from development due to the fact that they improve air and water quality and make available habitat for an extensive variety of plants and animals.

Unfortunately, these areas are frequently susceptible to development due to the fact that it is difficult to estimate the economic benefits of cleaner air, cleaner water, and the majority of other environmental benefits of these ecosystems-the plants and animals of a natural community and their physical environment.

Current Types Of Conservation
There are a lot of fundamental conservation methods utilized in the protection of global natural resources. Although each resource has a unique set of conservation problems and solutions, all resources are interconnected in a complex and little-understood web.

Scientists have learned that damaging one thread of the web may weaken the entire structure. It is important that this connectivity be addressed in the search for solutions to resource shortages.

It would be impractical to work toward the conservation of soil, for instance, without considering the needs and effects of nearby water and vegetation resources.

1. Conservation of Biodiversity, or biological diversity
This refers to the number and variety of various organisms and ecosystems in a particular area. Preserving biodiversity is crucial for ecosystems to react flexibly to damage or change.

For instance, a single-species corn crop may be easily destroyed by a particular insect or disease, but if a lot of various species of corn are planted in the field, a few of them may resist the insect or disease and survive.

Humans gain a lot from the varieties of medicines, crops, and other materials made available by biodiversity. About 40 percent of our present day pharmaceutical medicines are obtained from plants or animals.

For example, a tiny plant from Madagascar, known as the rosy periwinkle, manufactures substances that are efficient in combating two deadly cancers, Hodgkin's disease and leukemia.

Unfortunately, human activities have to a large extent reduced biodiversity all over the world especially the happenings of the 20th century. The highest threat to biodiversity is loss of habitat as humans develop land for agriculture, grazing livestock, industry, and habitation.

The major drastic damage has taken place in the tropical rain forests, which encompass less than seven percent of the Earth's surface but posses above half of the planet's biodiversity.

2. Conservation of Forest
Forests make available a lot of social, economic, and environmental benefits. Additionally to timber and paper products, forests make available wildlife habitat and recreational opportunities, avert soil erosion and flooding, aid in the provision of clean air and water, and possess fantastic biodiversity.

Forests are as well a crucial defense against global climate change. Through the process of photosynthesis, forests create life-giving oxygen and make use of enormous amounts of carbon dioxide, the atmospheric chemical majorly responsible for global warming.

By the reduction of circulating carbon dioxide in the atmosphere, forests may lessen the effects of global warming.

Irrespective of this large areas of thickest forests in the world have been cleared for wood fuel, timber products, agriculture, and livestock. These forests are quickly disappearing.

The countries with the majority of tropical forests tend to be developing and overpopulated nations in the southern hemisphere. As a result of deprived economies, people resort to clearing the forest and planting crops in order to survive.

Although there have been efficient efforts to stop deforestation directly through a lot of multinational organizations that are responsible for abusive logging, the major efficient conservation policies in these countries have been efforts to reduce poverty and make bigger access to education and health care.

3. Conservation of Soil
Soil is a mixture of mineral, plant, and animal materials. It is necessary for the majority of plant growth and is the essential resource for agricultural production. Humans have increased soil erosion processes by developing the land and clearing away the vegetation that holds water and soil in place.

The rapid deforestation occurring in the tropics is particularly damaging because the thin layer of soil that remains is fragile and quickly washes away when exposed to the heavy tropical rains.

4. Conservation of Water
Clean freshwater resources are necessary for drinking, bathing, cooking, irrigation, industry, and for plant and animal survival. Regrettably, the world supply of freshwater is dispersed unevenly. Constant water shortages occur the majority of African country and drought is widespread over the majority of the globe.

5. Conservation of Energy
Every human culture needs the production and utilization of energy—that is, resources with the capability generate work or power. Energy is utilized in transportation, heating, cooling, cooking, lighting, and industrial production.

The world energy resources depends on a lot of various resources which includes traditional fuels like firewood and animal waste, which are important energy sources in various developing countries. Fossil fuels account for more than 90 percent of global energy production but have a lot of problems.

They are nonrenewable and their use causes air pollution. Coal power plants for an example have been one of the worst industrial polluters since the onset of Industrial Revolution of the 19th century.

In addition, mining or drilling for fossil fuels has lead to extended environmental damage.

There is a global need to increase energy conservation and the use of renewable energy resources.

Renewable energy alternatives like waterpower (using the energy of moving water, like rivers), solar energy (using the energy from the sun), wind energy (using the energy of the wind or air currents), and geothermal energy (using energy contained in hot-water deposits within the Earth's crust) are effective and practical but are greatly underutilized due to the ready accessibility of cheap, nonrenewable fossil fuels in industrial countries.

In addition to making use of alternative energy resources like solar and wind power, energy conservation measures as well encompass enhancing energy efficiency. For example, transportation accounts for the majority of the oil consumption in the United States.

Encouraging the expansion and use of public transportation systems and carpooling considerably increases energy efficiency. In the home, energy can be conserved by turning down thermostats, switching off unnecessary lights, insulating homes, and making use of less hot water.