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

Views: 34

Properties Of Acids And Bases

Substances can be categorize a substance as an acid or a base according to the properties displayed.

Properties of Acids

  1. They have sour taste
  2. They give the following  characteristic colors in indicators
  3. Acids are corrosive in  Nature

The ability of acids to attack various substances like metals, metal oxides and hydroxides is referred to as their corrosive nature.

  1. They dissociate in water to produce hydrogen ions

Acids  dissociate in water to produce hydrogen ions (H+) which are responsible for all their characteristic properties. These ions do not exist as H+ in the solution but combine with water molecules as shown below:

H+    +

H2O  →

H3O+

The H3O+ ions are called hydronium ions. These ions are also represented as H+(aq).

On the basis of the extent of dissociation occurring in their aqueous solutions, acids are classified as strong and weak acids

  1. Acid reacts with metals  to produce hydrogen gas.

During such reactions metal displaces hydrogen from acids and hydrogen gas is released. The metal combines with the remaining part of the acid and forms a compound called a salt, thus,

Acid + Metal  → Salt + Hydrogen gas

For example, the reaction between zinc and dil. sulphuric acid can be written as:

Zn

+

H2SO4

 →ZnSO4

+

H2 
  1. Acids react with Carbonates or Hydrogen carbonate to give carbon dioxide gas

 The respective reactions are:

Na2CO3(s)  +  2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g)↑

NaHCO3(s)  +  HCl(aq)→ NaCl(aq)  +  H2O(l)  +  CO2 (g) ↑

On passing the evolved carbon dioxide gas through lime water, Ca(OH)2, the later turns milky due to the formation of white precipitate of calcium carbonate         

Ca(OH)2(aq)+ CO2(g) →CaCO3(s) + H2O(l)

If excess of carbon dioxide gas is passed through lime water, the white precipitate of calcium carbonate disappears due to the formation of water soluble calcium hydrogen carbonate.

                 CaCO3(s) +H2O(l)  +  CO2(g) → Ca(HCO3)2(aq)

Thus, we can summarize that,

      Metal carbonate + Acid → Salt + Water + Carbon dioxide

and  

    Metal hydrogen carbonate + Acid → Salt + Water + Carbon dioxide

  1. Acids react with metal oxides to produce salt and water

The reaction between copper oxide and dilute hydrochloric acid results in the formation of copper (II) chloride (cupric chloride) which is a salt of copper. This salt forms bluish green solution. The reaction is:

CuO(s)  + 2HCl(aq)   →  CuCl2(aq)  +  H2O(l)

Many other metal oxides like magnesium oxide (MgO) and calcium oxide (CaO) or quick lime also react with acid in a similar way. For example,

CaO(s) + 2HCl(aq)  → CaCl2(aq)  +  H2O(l)

So, we can summarize with a general reaction between metal oxides and acids as:

                         Metal oxide + Acid  → Salt + Water

  1. Acids reacts with bases  to give salt and water

when dilute acids  is added to dilute basic  solution, they two react with each other to give salt and water. The process is therefore called neutralization. It results in the formation of salt and water. The reaction betweenhydrochloric acid and sodium hydroxide forms sodium chloride and water.

HCl(aq)+ NaOH(aq) →NaCl(aq)  +  H2O(l)

Similar reactions occur with other acids and bases. For example ,sulphuric acid and potassium hydroxide react to form potassium sulphate and water.

H2SO4(aq)  +  2KOH(aq)  → K2SO4(aq)  +  2H2O(l)

In general, the reaction between and acid and a base can be written as:      Acid  +  Base → Salt  +  Water

Properties of Bases

The following are the characteristic properties of bases:

  1. Bases have a bitter taste and their solutions are soapy to touch.
  2. Bases are caustic nature

Strong bases like sodium hydroxide and potassium hydroxide are corrosive towards organic matter and break down the proteins of the skin and flesh to a pasty mass. This action is called caustic action and it is due to this property that sodium hydroxide is called ‘caustic soda’ and potassium hydroxide is called ‘caustic potash’. The term ‘caustic’ is not used for corrosive action of acids.

  1. Each indicator shows characteristic colour in presence of bases as given below

Indicator

Colour in basic medium

Litmus

Blue

Phenolphthalein

Pink

Methyl orange

Yellow
  1. Bases  dissociates in water and conduct electricity

Aqueous solutions (solution in water) of bases conduct electricity which is due to the formation of ions. Like acids, bases also dissociate on dissolving in water. Bases produce hydroxyl ions (OH–) which are responsible for their characteristic properties.

The bases which are soluble in water and give OH– ions in their aqueous solution are called alkalis. All alkalis are bases but all bases are not alkalis. On the basis of the extent of dissociation occurring in their solution, bases are classified as strong and weak bases.

  1. Strong and Weak Bases

Bases are classified as strong and weak bases  based on the extent of their dissociation in water  

  1. Reaction of bases with metals

Like acids, bases also react with active metals liberating hydrogen gas. Such reactions can also be studied with the help of activity 8.2 given earlier. For example, sodium hydroxide reacts with zinc as shown below:

              Zn(s)  +  2NaOH(aq)  →Na2ZnO2(aq)  +  H2(g) ↑

  1. Reaction of Bases with non-metal oxides

Bases react with oxides of non-metals like CO2, SO2, SO3, P2O5 etc. to form salt and water.

For example,

Ca(OH)2(aq) + CO2(g) → CaCO3(s) +  H2O(l)

The reaction can be written in a general form as:

Base + Non-metal oxide→  Salt + Water

  1.  Reaction of bases with acids

We have learnt the mutual reaction between acids and bases in previous section. Such reactions are called neutralization reactions and result in the formation of salt and water. The following are some more examples of neutralization reactions:

HCl(aq)  + KOH(aq)  → KCl(aq) + H2O(l)

       H2SO4(aq)  + 2NaOH(aq) → Na2SO4(aq) + 2H2O(l)

Strength  and Concentration Of Acids And Bases

Some acids and bases are stronger than others eg

     HI >HBr >HCl

     NaOH >CaOH2>NH4OH

All acids liberates hydrogen gas .if equal volume of acids are used  and if the amount of the hydrogen gas liberated is measured  ,it shall be found that the volume of H2 liberated  varies depending on the type of acid used.

These shows that the greater the reactivity of acids   must be the result of the amount of H2 gas liberated. The strength of acid  is therefore measured in terms of H+ concentration  of the solution. The scale of acid strength  ranges  from very strong acid HI,HBr,Hcl, through  an intermediate range  down to weak acid eg acetic acid . The strength of bases is similarly assessed  basing on the same reasoning  for OH- .

Strong acids readily dissociate in water and gives or transfer all their H+  to water  to form H3O+ ions  Acids are therefore strong electrolytes because they completely dissociate  to give ions . In contrast , weak acids   do not readily dissociate  or transfer its H+ ions. Similarly strong bases are those that completely dissociate to give all their OH- whereas weak bases do not completely dissociate

Concentrated and dilute acids and bases refer to the amount of water added to that particular acid or base .Concentration is measured in molarity. Concentrated acid is that which have less amount of water dissolved  in large amount of acid  while dilute acid have  large amount of water is dissolved  in less amount of base

SALTS

Salts are ionic compounds made of a cation other than H+ ion and an anion other than OH– ion.

Formation of salts

Salts are formed in many reactions involving acids and bases.

  1. By Neutralization of acids and bases

Salts are the product of a neutralization reaction( produced besides water).

For example,

Base

Acid

Salt

Water

NaOH

+

HCl

→   NaCl

+

H2O

KOH

+

HNO3

→   KNO3

+

H2O

In general,   MOH

+

HX

→MX

+

H2O

In all the above cases we can see that the positively charged cation of the salt comes from the base. Therefore, it is called the ‘basic radical’. The negatively charged anion of the salt comes from the acid. It is therefore, called the ‘acid radical’ of the salt. For example, in the salt NaCl, the cation Na+ comes from the base NaOH and is its basic radical and the anion Cl– comes from the acid HCl and is its ‘acid radical’.

  1. By action of acids on metals

In a reaction between an acid and a metal, salt is produced along with hydrogen,

Zn

+   H2SO4

→  ZnSO4+

H2
  1. By action of acids on metal carbonates and hydrogen carbonates

Salts are produced in reactions between acids and metal carbonates and hydrogen carbonates (bicarbonates) along with water and carbon dioxide.

CaCO3

+

2HCl

 →   CaCl2

+

H2O

+

CO2

NaHCO3

+

HCl

 →    NaCl

+

H2O

+

CO2

Join the conversation
Previous
Next

You cannot copy content of this page