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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Molarity

standard solutions are commonly expressed in terms of molar concentrations or molarity (M). Molarity (M) is the amount of a substance in a certain volume of solution. Molarity is defined as the moles of a solute per liters of a solution. Molarity is also known as the molar concentration of a solution

Therefore ,standard solutions are specified in terms of the number of moles of solute dissolved in 1 litre of solution; for any solution,   

  • Molarity (M) =    Moles of solute
  •                             Volume of solution in litres

Example

  • If 5.00g of sodium chloride is dissolved in exactly 250 cm3 of water in a calibrated volumetric flask,
  • (a) what is the concentration in g/dm3?
  •      Volume         =    250/1000 = 0.25 dm3
  • Concentration  =    mass / volume
  •                         = 5/0.25  
  •                         = 20 g/dm3

What is the molarity of the solution?

  • Ar(Na) = 23, Ar(Cl) = 35.5,
  • so Mr(NaCl) = 23 + 35.5 = 58.5
  • mole NaCl = 5.0/58.5 = 0.08547
  • volume = 250/1000 = 0.25 dm3
  • molarity = mol of solute / volume of solvent
  • Molarity = 0.08547/0.25
  • = 0.342 mol/dm3

5.95g of potassium bromide was dissolved in 400cm3 of water.

  • (a) Calculate its molarity. [Ar‘s: K = 39, Br = 80]
  • moles = mass / formula mass, (KBr = 39 + 80 = 119)
  • mol KBr = 5.95/119 = 0.050 mol
  • 400 cm3 = 400/1000 = 0.400 dm3
  • molarity = moles of solute / volume of solution
  • molarity of KBr solution = 0.050/0.400 = 0.125 mol/dm3
  • (b) What is the concentration in grams per dm3?
  • concentration = mass / volume, the volume = 400 / 1000 = 0.4 dm3
  • concentration = 5.95 / 0.4 = 14.9 g/dm3

What mass of sodium hydroxide (NaOH) is needed to make up 500 cm3 (0.500 dm3) of a 0.500 mol dm-3 (0.5M) solution? [Ar‘s: Na = 23, O = 16, H = 1]

  • 1 mole of NaOH = 23 + 16 + 1 = 40g
  • molarity = moles / volume, so mol needed = molarity x volume in dm3
  • 500 cm3 = 500/1000 = 0.50 dm3
  • mol NaOH needed = 0.500 x 0.500 = 0.250 mol NaOH
  • therefore mass = mol x formula mass
  • = 0.25 x 40 = 10g NaOH required
  • How many moles of H2SO4 are there in 250 cm3 of a 0.800 mol dm-3 (0.8M) sulphuric acid solution?

What mass of acid is in this solution?

  •                                 [Ar‘s: H = 1, S = 32, O = 16]
  • (a) molarity = moles / volume in dm3, rearranging equation for the sulfuric acid
  • mol H2SO4 = molarity H2SO4 x volume of H2SO4 in dm3
  • mol H2SO4 = 0.800 x 250/1000 = 0.200 mol H2SO4
  • (b) mass = moles x formula mass
  • formula mass of H2SO4 = 2 + 32 + (4×16) = 98
  • 0.2 mol H2SO4 x 98 = 19.6g of H2SO4 
  •  

A solution of calcium sulphate (CaSO4) contained 0.500g dissolved in 2.00 dm3 of water.

  • Calculate the concentration in (a) g/dm3, (b) g/cm3 and (c) mol/dm3.
  • (a) concentration = 0.500/2.00 = 0.250 g/dm3,
  • then since 1dm3 = 1000 cm3
  • (b) concentration = 0.250/1000 = 0.00025 g/cm3  
  • (or from 0.500/2000)
  • (c) At. masses: Ca = 40, S = 32, O = 64,
  • formula mass CaSO4 = 40 + 32 + (4 x 16) = 136
  • moles CaSO4 = 0.5 / 136 = 0.00368 mol in 2.00 dm3 of water
  • concentration CaSO4 = 0.00368 / 2
  •  = 0.00184 mol/dm3

Error in Titration Calculations

Different methods are used to determine the equivalence point of a titration. No matter which method is used, some error is introduced, so the concentration value is close to the true value, but not exact. For example, if a colored pH indicator is used, it might be difficult to detect the color change. Usually, the error here is to go past the equivalence point, giving a concentration value that is too high.

Another potential source of error when an acid-base indicator is used is if water used to prepare the solutions contains ions that would change the pH of the solution. For example, if hard tap water is used, the starting solution would be more alkaline than if distilled deionized water had been the solvent.

If a graph or titration curve is used to find the endpoint, the equivalence point is a curve rather than a sharp point. The endpoint is a sort of “best guess” based on the experimental data.

The error can be minimized by using a calibrated pH meter to find the endpoint of  an acid-base titration rather than a color change or extrapolation from a graph.


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