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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Thin Layer Chromatography

 Thin Layer Chromatography is a technique used to isolate non-volatile mixtures. The experiment is conducted on a sheet of aluminium foil, plastic, or glass which is coated with a thin layer of adsorbent material. The material usually used is aluminium oxide, cellulose, or silica gel.

Like other chromatographic techniques, thin-layer chromatography (TLC) depends on the separation principle. The separation relies on the relative affinity of compounds towards both the phases. The compounds in the mobile phase move over the surface of the stationary phase. The movement occurs in such a way that the compounds which have a higher affinity to the stationary phase move slowly while the other compounds travel fast. Therefore, the separation of the mixture is attained. On completion of the separation process, the individual components from the mixture appear as spots at respective levels on the plates. Their character and nature are identified by suitable detection techniques.

On completion of the separation, each component appears as spots separated vertically. Each spot has a retention factor (Rf) expressed as:

Rf = dist. travelled by sample / dist. travelled by solvent

The factors affecting retardation factor are the solvent system, amount of material spotted, absorbent and temperature.

 TLC is one of the fastest, least expensive, simplest and easiest chromatography technique.

                 Diagram of Thin Layer Chromatography

The different components required to conduct the procedure along with the phases involved.

  1. Thin Layer Chromatography Plates – ready-made plates are used which are chemically inert and stable. The stationary phase is applied on its surface in the form of a thin layer. The stationary phase on the plate has a fine particle size and also has a uniform thickness.
  2. Thin Layer Chromatography Chamber – Chamber is used to develop plates. It is responsible to keep a steady environment inside which will help in developing spots. Also, it prevents the solvent evaporation and keeps the entire process dust-free.
  3. Thin Layer Chromatography Mobile phase – Mobile phase is the one that moves and consists of a solvent mixture or a solvent. This phase should be particulate-free. The higher the quality of purity the development of spots is better.
  4. Thin Layer Chromatography Filter Paper – It has to be placed inside the chamber. It is moistened in the mobile phase.

Procedure for Thin Layer Chromatography

The stationary phase that is applied to the plate is made to dry and stabilize.

To apply sample spots, thin marks are made at the bottom of the plate with the help of a pencil.

Apply sample solutions to the marked spots.

Pour the mobile phase into the TLC chamber and to maintain equal humidity, place a moistened filter paper in the mobile phase.

Place the plate in the TLC chamber and close it with a lid. It is kept in such a way that the sample faces the mobile phase.

Immerse the plate for development. Remember to keep the sample spots well above the level of the mobile phase. Do not immerse it in the solvent.

Wait till the development of spots. Once the spots are developed, take out the plates and dry them. The sample spots can be observed under a UV light chamber.

Applications of Thin Layer Chromatography 

  1. The qualitative testing of Various medicines such as sedatives, local anaesthetics, anticonvulsant tranquilisers, analgesics, antihistamines, steroids, hypnotics is done by TLC.
  2. TLC is extremely useful in Biochemical analysis such as separation or isolation of biochemical metabolites from its blood plasma, urine, body fluids, serum, etc.
  3. Thin layer chromatography can be used to identify natural products like essential oils or volatile oil, fixed oil, glycosides, waxes, alkaloids, etc.
  4. It is widely used in separating multicomponent pharmaceutical formulations.
  5. It is used to purify of any sample and direct comparison is done between the sample and the authentic sample.
  6. It is used in the food industry, to separate and identify colours, sweetening agent, and preservatives
  7. It is used in the cosmetic industry.
  8. It is used to study if a reaction is complete

Disadvantages Of Thin Layer Chromatography:

  1. Thin Layer Chromatography plates do not have longer stationary phase.
  2. When compared to other chromatographic techniques the length of separation is limited.
  3. The results generated from TLC are difficult to reproduce.
  4. Since TLC operates as an open system, some factors such as humidity and temperature can be consequences to the final outcome of the chromatogram.
  5. The detection limit is high and therefore if you want a lower detection limit, you cannot use TLC.
  6. It is only a qualitative analysis technique and not quantitative.
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