Course Content
Introduction to Environmental Chemistry
Environmental chemistry is the study of the chemical and biochemical phenomena that occur in nature. It involves the understanding of how the uncontaminated environment works, and which naturally occurring chemicals are present, in what concentrations and with what effects. Environmental chemistry; is the study of sources, reactions, transport, effects and fate of chemical species in water, soil and air environment as well as their effects on human health and natural environment
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Introduction
Origin of the solar System
Cosmology; is the branch of astronomy involving the study of the of the universe and the solar system. Cosmo-chemistry ;( chemical cosmology); is the study of chemical composition of the matter in the universe and the process that led to those compositions The solar system is made up of the sun (a star) with nine planets orbiting around it. These planets together with all the other heavenly bodies moving around or between individual planet form members of the solar system. Other heavenly body include; asteroids, comets, meteors, meteorites and satellites such as moon. The solar system does not include other stars .
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Origin of The Universe and Solar System
Solutions
Solutions are defined as homogeneous mixtures that are mixed so thoroughly that neither component can be observed independently of the other. The major component of the solution is called solvent, and the minor component(s) are called solute.
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Introduction
Solubility of Solutions
Solubility Product
Solution Concentrations
Chemical Equilibria
Chemical equilibrium in the environment refers to the state where the rates of forward and reverse reactions of a chemical reaction reach a balance. In this state, the concentrations of reactants and products remain constant over time, although the reactions continue to occur.
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Introduction
The Concept of Equilibrium
Relation Between Chemical Kinetics and Chemical Equilibrium
Factors Affecting Chemical Equilibrium
Laws of Chemical Equilibria
Phase Interactions
Phase interactions in solutions refer to the behavior and changes that occur when two or more substances (solutes and solvents) mix together to form a homogeneous mixture. These interactions are related to the different phases of matter, such as solids, liquids, and gases, and how they interact and transform during the process of solution formation.
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Introduction
 Phase interactions
Colligative Properties of Solutions
COLLIGATIVE PROPERTIES OF SOLUTIONS Colligative properties are physical properties of solutions that depend on the concentration of solute particles, rather than the specific identity of the solute. The four colligative properties that can be exhibited by a solution are: 1.Boiling point elevation 2.Freezing point depression 3.Relative lowering of vapour pressure 4.Osmotic pressure
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Introduction
Colligative Properties Examples
Introduction To Organic Chemistry
Organic chemistry is the study of carbon containing compounds and their properties. This includes the great majority of chemical compounds on the planet, but some substances such as carbonates and oxides of carbon are considered to be inorganic substances even though they contain carbon.
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Introduction
The IUPAC Naming (nomenclature) 
Alkyl halides, Alkenes and Alkynes
Alcohols , Ethers, Aldehydes and Ketones
Carboxylic Acids, Esters and Amines
Simple Organic Molecules in the Environment
Soil Chemistry and Pollution
soil
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Introduction to Soil Chemistry
Chemical Characteristics of Soil
Biological Characteristics of Soil
Physical Characteristics of Soil
Soil Salinity, Conductivity and Ion Exchange Capacity
Soil Pollution
Water Chemistry and Polution
Water Chemistry
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Water and the Environment
Water Chemistry
Characteristics and Properties of Water
Portable water 
Water pollution
Water Quality Analysis
Biological Oxygen Demand (BOD)
Chemical Oxygen Demand (COD)
Air Quality and Pollution
Air Quality and Pollution
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Air Quality
Testing Air Quality
Biodegradation
Biodegradation
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Biodegradation
Mechanisms of Biodegradation 
Role of Microorganisms in Biodegradation
BioGeoChemical Cycles
BiogeoChemical Cycles
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Biogeochemical cycles
The Water Cycle
The Carbon Cycle
The Nitrogen Cycle
The Phosphorus Cycle
The Sulfur Cycle
Introduction To Environmental Chemistry
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FACTORS THAT AFFECT CHEMICAL EQUILIBRIUM

Le Chatelier’s Principle

Le Chatelier’s principle states that any stress on the system (∆P, ∆ T, change in reactant or product concentration) causes the system to adjust so as to partially offset the change and establish a new equilibrium.

Changes In Concentration

The effect of concentration changes can be understood by considering the effect of changes in reactant and product molecule collisions or by solving the Law of Mass Action.

The effects of concentration changes can be determined qualitatively by inspection of the equilibrium expression or by calculating Qc values for initial reactant and product concentration in the equilibrium expression.

Changes In Volume and Pressure

Pressure has a small and generally negligible effect on equilibria in the liquid or solid state reactions. (An exception is the huge pressures involved in the graphite-diamond transition.)

In gas phase reactions, pressure changes affect the equilibrium if the reaction produces a change in the number of moles of gas.

Pressure change can be brought about by changing the volume of the system or by adding or removing one of the reaction components.

Example: If a gas reaction causes the number of moles of gas to double, the system pressure at constant volume will double.

According to Le Chatelier’s principle, an imposed increase in the system pressure will drive the reaction to the left (restoring the system equilibrium. This pressure change can be created by a piston that changes the system volume.

The CaCO3(s) ↔ CaO(s) + CO2(g) equilibrium will shift left with a pressure increase

The H2(g) + I2(g) ↔ 2HI equilibrium is unaffected by pressure changes.

The CH3COOH(aq) + NaOH(aq) → CH3COONa(aq) + H2O(l) equilibrium is unaffected by pressure.

The 3H2(g) + N2(g) ↔ 2 NH3(g) equilibrium shifts right with a pressure increase.

What happens to the same reactions when the pressure change is caused by adding or removing one of the reaction components?

Changes In Temperature

Equilibrium constants change with changes in temperature. (K is only constant for constant T.) In general, a temperature increase favors an endothermic reaction and a temperature decrease favors an exothermic reaction. To remember this, think of heat as a reactant or product in a reaction and think how its addition or removal form a system will affect the outcome.

              Heat + A ↔ B (endothermic)

Increasing temperature causes the equilibrium to shift to the right since heat is needed to force the reaction.

The Effect of A Catalyst

A catalyst affects only the speed of a reaction. A catalyst has no effect on the position of equilibrium.

A catalyst has an equal effect on lowering the Eact of the forward and the backward reaction


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