Course Content
Matter
OBJECTIVES By the end of this topic, the trainee should be able to 1.Define matter 2.Explain state of matter 3.Distinguish between physical and chemical changes 4.Explain the gas laws
0/4
Introduction
States of Matter
Physical and Chemical Properties and Changes
The Gas Laws
Atoms , Elements and Compounds
OBJECTIVES By the end of this topic , the trainee should be able to; 1.Define Elements, Compounds and Mixtures 2.Describe the structure of an atom 3.Describe how to determine the Atomic number ,Mass number and Isotopes
0/3
Introduction
Atomic Structure
Atomic Structure of Isotopes
The Periodic Table
OBECTIVES By the end of this topic, the trainee should be able to : 1.State the historical contribution on development of the periodic table 2.Explain the periodic trends of elements and their compounds 3.State the diagonal relationships of the periodic table
0/3
Introduction
Families of the Periodic Table
The Periodic Trends
The S-Block Element
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain the chemistry of group I and II elements 2.State the application of group I and two elements and their compounds
0/4
Introduction
Electronic Configuration of S-Block Elements
Physical Properties of S-Block Elements
Chemical Properties of S-Block Elements
Chemical Bonds
OBJECTIVES By the end of these topic, the trainee should be able to 1.Identify different types of bonds 2.Describe their properties
0/2
Introduction
Types and Properties of Chemical Bonds
Chemical Equilibrium
OBJECTIVES By the end of this topic , the trainee should be able to : 1.Define chemical equilibria 2.Explain types of equilibria 3.Determine equilibrium constant 4.Describe factors affecting chemical equilibrium
0/6
Introduction
Measuring Equilibrium Rates
Equilibrium Basics
Types of equilibria
Predicting The Direction of a Reaction
Factors Affecting equilibrium
Introduction To Organic Chemistry
By the end of this topic , the trainee should be able to : 1.Explain the aspects of organic chemistry 2.Describe hydrocarbons 3.Classify organic molecules explain chemical reactions of simple organic molecules 4.Explain the properties , synthesis and uses of simple organic molecules
0/10
Introduction
Functional Groups
Alkanes
Alkenes and Alkynes
Alkanols(Alcohols)
HaloAlkanes
Alkanals and Alkanones
Carboxylic Acids
Esters
Amines
Acids, Bases and Salts
OBJECTIVES By the end of this session , the trainee should be able to : 1.State properties of acids and bases 2.Differentiate between strong and weak acids 3.Explain types and properties of salts
0/2
Introduction
Properties Of Acids And Bases
PH Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define the term PH 2.Explain the basic theory of PH 3.State the relationship between PH and color change in indicators 4.Explain the term buffer solution 5.Describe the preparation of buffer solutions 6.State the application of buffer solutions
0/5
Introduction
Neutral, acidic and basic solutions
PH and Its Importance
Determination Of PH
Buffer Solutions
Sampling and Sample Preparation
OBJECTIVE By the end of this topic, the trainee should be able to : 1.Define the terms used in sample preparation 2.State the importance of sampling 3.Describe the techniques of sampling 4.Describe the procedure for sample pre-treatment 5.State sample storage methods
0/5
Introduction
Types of Samples and Sampling
Sample preparation
Sample Losses During Preparation
Sample Identification and Storage
Separation Techniques
OBJECTIVES By the end of this topic , the trainee should be able to : 1.Define separation, extraction and purification 2.Describe the separation , extraction and purification techniques 3.Explain the methods of determining purity of substances
0/2
Introduction
Separation Techniques
Heating and Cooling Techniques
OBJECTIVES To identify various techniques used for heating and cooling substances in the laboratory
Heating and Cooling Techniques
OBJECTIVES To identify various techniques used for heating and cooling substances in the laboratory
0/1
Heating and Cooling Techniques used in the lab
Distillation Techniques
By end of this topic, Trainee should be able to : 1. Define distilation 2. State and explain various distillation techniques 3. Outline Various distillation techniques 4. Outline the applications of Distillation techniques
0/3
Introduction
Types of Distillation Techniques 
Distillation and Reflux Condensers
Crystallization Techniques
OBJECTIVES By the end of the topic, the learner should be able to: 1.To define crystallization 2.To describe crystallization process 3.To carry out crystallization procedure
0/1
Crystallization Technique
Solvent Extraction Techniques
OBJECTIVES By the end of the topic, the learner should be able to 1.Define solvent extraction 2.Explain terms used in solvent extraction 3.Describe methods of solvent extraction 4.Describe selection of appropriate solvents for solvent extraction 5.Determine distribution ration 6.Outline factors actors influencing the extraction efficiency 7.Describe Soxhlet extraction
0/1
Introduction
Chromatography Techniques
OBJECTIVES By the end of this topic, the learner should be able to: 1.Define chromatography techniques 2.Explain terms used in chromatography techniques 3.Describe principles of chromatography techniques 4.Explain types of chromatography techniques 5.Carry out chromatography experiments 6.Determine RF factor 7.Outline electrophoresis
0/6
Introduction to Chromatography Techniques
Types of Chromatography Techniques
Thin Layer Chromatography
Column Chromatography
Retardation Factor (Rf)
Gas-Liquid Chromatography
Titrimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define terms used in titrimetric analysis 2.Describe types of titrimetric analysis 3.Balance chemical reactions 4.Work out calculations involved in titrimetric analysis
0/6
Introduction
Requirements For Titrimetric Analysis
Titration procedure:
Molarity
Apparatus for titrimetric analysis
Classification Of Reactions In Titrimetrlc Analysis
Redox Titration
Redox Titration is a laboratory method of determining the concentration of a given analyte by causing a redox reaction between the titrant and the analyte. Redox titration is based on an oxidation-reduction reaction between the titrant and the analyte. It is one of the most common laboratory methods used to identify the concentration of unknown analytes. Redox reactions involve both oxidation and reduction. The key features of reduction and oxidation are discussed below.
0/5
Introduction
The oxidation number 
Balancing Redox Reactions
Examples Of Redox Titration
Standardization of Redox solutions
Complexiometric Titration
omplexometric Titration or chelatometry is a type of volumetric analysis wherein the colored complex is used to determine the endpoint of the titration. The method is particularly useful for determination of the exact number of a mixture of different metal ions, especially calcium and magnesium ions present in water in solution .
0/5
Introduction to Complexiometric Titration
EDTA titration
Types of EDTA titrations
EDTA titration experiment 
Mechanism of action of indicator:
Gravimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define gravimetric analysis 2.Describe the principles of gravimetric analysis 3.Describe the steps involved in gravimetric analysis 4.Explain factors affecting gravimetric analysis 5.Describe the equipments and apparatus used in gravimetric analysis 6.Carry out gravimetric analysis
0/8
Introduction
Principles Of Gravimetric Analysis
Determination of Mass in gravimetric analysis
Factors Affecting Separation Of Metals And Compounds
Preparation of pure precipitates
Example of gravimetric Analysis
Gravimetric Calculations
Draft Lesson
Calorimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define terms and units used in thermochemistry 2.Determine enthalpy changes in chemical reactions 3.Determine heat capacity and specific heat capacity 4.Compare calorific values of different materials 5.Determine different heat reactions 6.Apply law of conservation of energy and Hess law in thermochemical calculations
0/4
Introduction
Calorimetry
Heat Capacity
Enthalpy of Phase Transitions
Chemistry Techniques for Science Laboratory Technicians
About Lesson

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Predicting The Direction of a Reaction

The reaction quotient, Qc can help keep track of reaction direction on changing some concentrations.

Kc is the constant at equilibrium; Q c is the value obtained with the nonequilibrium initial or forced values given by the problem. If Kc and Qc are equal, then the system is already at equilibrium. If Qc> Kc, then the reaction must shift to the left before equilibrium is reached (products must back react to become reactants). If Qc< Kc, then the system must shift to the right for the system to attain equilibrium (reactants must turn into products).

Ex: The Ka for the dissociation of acetic acid is 1.8 x 10-5. HA(aq) ↔ A-1(aq) + H+1(aq)

If a system contains [A-1 ] = 2.0 x 10-4M, [H+1] = 1.5 x 10-5 M and [HA] = 0.55 M, determine whether the system is in equilibrium or not and in what direction it must shift to put it into equilibrium. Qc = 5.5 x 10-9 (compared to Ka = 1.8 x 10-5) so the system must shift to the right (more product) to attain equilibrium.

Calculating Equilibrium Concentrations

Use the Law of Mass action equation

                         K = [C]c [D]d/ [A]a [B]b

If all the reactant and product concentrations are known and the balanced equation is known, then a value for K can be easily calculated.

When K is known, the equilibrium concentration values can be calculated knowing one or more initial concentration values. Use the balanced equation to relate initial and equilibrium values. The resulting equation may involve the quadratic formula.

Ex: For the dissociation of any weak acid,  HA(aq) ↔ H+1(aq) + A-1(aq)

  • = [H+1] · [A-1]/ [HA] Suppose K = 4.2 x 10-7and imagine a system where the initial HA concentration is 0.100M. What are the equilibrium concentrations of HA, H+1 and A-1?

At equilibrium, let [A-1] = [HA] = X. Let [HA] = 0.100-X

(Sometimes, X is so small that the [HA] change can be ignored and equilibrium [HA] = 0.001M also. See if this is true in this case.)

4.4 x 10-7 = X2/(0.100) X2 = 4.4 x 10-8 X = 2.1 x 10-4M = [A-1]

 = [HA] [HA] = (0.100 -X) = 0.100 – 0.00021 ≈ 0.001M (The assumption holds.)

To check the answer, plug the numbers into the K expression to see if the original K value is obtained.

Other calculations may be more difficult and require use of the quadratic formula.

Example : Ca+2  + EDTA-2  ↔ CaEDTA K = 4.80

Suppose initial [Ca+2] = 0.1000 M and initial [EDTA-2] = 0.0500M, what are the equilibrium concentrations of Ca+2, EDTA-2 and CaEDTA?

Let X = [CaEDTA], 0.0100 – X = [Ca+2] and 0.0500 -X = [EDTA2].

= [CaEDTA] / [Ca+2] · [EDTA-2] = 9.80

 = X/(0.0100 – X)(0.0500 – X)

  X = 9.80(5.00 x 10-4 – 0.0600X + X2)

X = 4.90 x 10-3 – 0.588X + 9.80X29.80X2 – 1.588X + 4.90 x 10-3

Using the quadratic equation, X =- 0.159 (physically impossible) and

X = 0.0032 (a plausible value) [CaEDTA] = 0.0032M, [Ca+2] = 0.0068M and [EDTA-2] = 0.0468M

The Position of Equilibrium

When a bunch of molecules are left alone, they reach a state of equilibrium. But that position of equilibrium can change if something happens to the molecules. Here’s a list of things that can change the equilibrium point:

  1. New molecules or substances are added that are not a part of the main reaction.
    2. The temperature of the system is changed.
  2. The pressure of the system is changed.
  3. The concentrations are changed, like adding more water to a solution or adding more of one reactant or product.
  4. There is a change in the total volume of the system.

Equilibrium doesn’t always mean that there are equal numbers of reactant and product molecules. Our equilibrium point may look like it is in the middle of the two concentrations, but it can be anywhere. It’s all about balance and finding a happy point. There are times when everything becomes a product, and other reactions where nothing happens. It all depends on the molecules and conditions of the system.

Le Chatelier Principle

Le chatelier, a French scientist came up with a principle for systems in equilibrium. The principle says that if you have a system in equilibrium and you do anything to it that messes up the equilibrium, the system will try to move back to the original state of equilibrium. Or, if you have a happy system and you make it unhappy, it will try to make itself happy again.
His exact words were, “A system in equilibrium, when subjected to a stress resulting from a change in temperature, pressure, or concentration, and causing the equilibrium to be upset, will adjust its position of equilibrium to relieve the stress and reestablish equilibrium.”

Catalysts

Reactions need a certain amount of energy in order to happen. If they don’t have it, the reaction probably can’t happen. A catalyst lowers the amount of energy needed so that a reaction can happen more easily. A catalyst is all about energy. If you fill a room with hydrogen gas (H2) and oxygen gas (O2), very little will happen. If you light a match in that room (or just produce a spark), most of the hydrogen and oxygen will combine to create water molecules (H2O). It is an explosive reaction. You can also add a catalyst to that room and get one little reaction started. In that situation, you could add a little palladium (Pd) to act as the catalyst.

The energy needed to make a reaction happen is called the activation energy. As everything moves around, energy is needed. The energy that a reaction needs is usually in the form of heat. When a catalyst is added, something special happens. Maybe a molecule shifts its structure. Maybe that catalyst makes two molecules combine and they release a ton of energy. That extra energy might help another reaction to occur in something called a chain reaction. You could also think of a catalyst like a bridge in some instances. Instead of letting reactions happen in the same (but faster) way, it can offer a new direction or chemical pathway in order to skip steps that require energy.

Catalysts are also used in the human body. They don’t cause explosions, but they can make very difficult reactions happen. They help very large molecules to combine. Catalysts lower the activation energy required for a reaction to occur. With the activation energy lower, the products can also combine more easily. Therefore, the forward and reverse reactions are both accelerated. It changes both rates and usually changes the equilibrium point.

Inhibitor  works in exactly the opposite way as catalysts. Inhibitors slow the rate of reaction. Sometimes they even stop the reaction completely. Inhibitor can be used  to make the reaction slower and more controllable. Without inhibitors, some reactions could keep going and going and going. If they did, all of the molecules would be used up. That would be bad, especially in your body.


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