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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 Common Heating and Cooling Techniques used in the lab

Heating and cooling is a common laboratory procedure. there are variety of methods used for heating , but  the choice of which heat source to use depends on several factors: 

  1. Availability (does your institution own the equipment?) 
  2. Rate of heating (do you want to heat gradually or quickly?)
  3. Flexibility of heating (does the heat need to be waved around an apparatus?) 
  4. Final temperature required (low boiling liquids require a different approach than high boiling liquids) 
  5. Flammability of the content

Safety is an important factor in making laboratory choices, it’s important to consider the flammability of the liquid to be heated. Almost all organic liquids (except halogenated solvents) are considered “flammable,” meaning they are capable of catching on fire and sustaining combustion. However, this doesn’t mean that all organic liquids will immediately ignite if placed near a heat source. Many liquids require an ignition source (a spark, match, or flame) in order for their vapors to catch on fire, a property often described by the liquid’s flash point. The flash point is the temperature where the vapors can be ignited with an ignition source. For example, the flash point of 70% ethanol is 16.6oC meaning it can catch on fire at room temperature using a match.

Some flammable substances  eg diethyl ether, pentane, hexane, and low-boiling petroleum ether have autoignition temperatures are also capable of autoignition.

 Autoignition temperature is the  temperature where the substance spontaneously ignites under normal pressure and without the presence of an ignition source.

This property is particularly insightful because it does not require a flame but only a hot area. It would be dangerous to boil these solvents on a hotplate as vapors could spill out of the container and ignite upon contact with the surface of the hotplate. In general, caution should be used when using a hotplate for heating any volatile, flammable liquid in an open vessel as it’s possible that vapors can overrun the hotplate’s and contact the heating element beneath, which may be hotter than 350oC. 

Bunsen Burners

Bunsen burners are generally used to rapidly heat high-boiling liquids with low flammability (such as water). It is important to know that they can reach temperatures of approximately 1500oC and can easily ignite most organic compounds. If an apparatus is improperly set up, or if there is a small gap that allows organic vapors to escape from an apparatus, these vapors can ignite with a burner. Therefore, it is generally recommended to use other heat sources to warm flammable organic liquids. Bunsen burners should never be used with highly flammable solvents such as diethyl ether.

Hotplates

Hotplates are perhaps the most versatile heat source in the laboratory and can be used to heat beakers, Erlenmeyer flasks, and various hot baths (water, sand, and oil baths).

Hotplates work by passing electricity through a heating element covered by a ceramic top.  The hotplate surface can reach temperatures up to 350oC, which is hot enough to ignite many low-boiling solvents. Diethyl ether, pentane, hexane, low-boiling petroleum ether, and acetone should therefore never be heated in an open vessel with a hotplate.

Caution should be used when heating any flammable organic liquid in an open vessel on a hotplate, as organic vapors may spill out of containers and ignite upon contact with the heating element, which may be hotter than the ceramic surface.

A steam bath

A steam bath is a relatively safe way to heat flammable organic liquids. They are designed to heat beakers, Erlenmeyer flasks, and round-bottomed flasks…

Water baths.

Water bath are most commonly used to heat solutions to 100oC (boiling baths). Hot plate may be used in heating. They may also be used to heat to lower temperatures, although it can be difficult to maintain a constant temperature. Water baths can be covered with aluminum foil to prevent excessive evaporation, or to prevent excess moisture from entering open vessels. Cold water baths can also be used to cool apparatus in a quick manner

Sand baths,

 Also heated on a hotplate, can be used to heat solutions to a wide variety of temperatures, from moderate to high temperatures (> 250oC).  A vessel containing the substance to be heated  should be buried in a sand bath as much as possible as the surface is often much cooler than the sand below. A s metal spatula can be used to pile the sand up to at least the height of liquid inside the flask. Sand takes a long time to heat up, and a long time to cool down. To save time, a sand bath may be preheated while an apparatus is assembled as long as it is preheated a distance away from volatile organic liquids.

If the sand overheats and causes a liquid to boil uncontrollably, the flask can be partially lifted out of the sand, or the sand moved with a metal spatula away from contact with the liquid. Sand will remain warm even after turning off the hotplate, and therefore flasks have to be lifted out of the sand bath in order to cool.

Oil baths 

Oil baths are much like water baths, but use silicone or mineral oils is used in order to enable temperatures hotter than the boiling point of water. Silicone oil baths can be heated to 250oC, while mineral oil baths can be heated to 300oC. Mineral oil is composed of mixtures of long-chain alkanes, and so is combustible. Direct contact with open flames should therefore be avoided.

Heating mantles

Heating mantles are a relatively safe way to heat flammable organic liquids in a round bottomed flask. The mantles are cup-shaped and designed for different sizes of round bottomed flask .If a mantle does not fit a round bottomed flask perfectly, sand can be added to ensure good thermal contact. Heating mantles take some time to warm up and also take some time to cool down. The mantle will remain warm even after turning off, and therefore flasks have to be removed from the mantle in order to cool.

Cooling bath.

On occasion a solution may need to be cooled: to minimize evaporation of volatile liquids, induce crystallization, or to favor a certain reaction mechanism. Several cold baths are used for certain applications, with the simplest being an ice bath. When preparing an ice bath, it is important to use a mixture of ice and water, as an ice-water slurry has better surface contact with a flask than ice alone. 

Sometimes salts are added to ice in order to create baths colder than 0oC .It is also quite common to cool a solvent with dry ice (solid CO2) in order to achieve dramatically colder baths. In dry ice baths, dry ice is added to the solvent until a portion of dry ice remains. The most common dry ice bath is made with acetone and dry ice, and achieves a cold bath of −7oc

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