Question 1 What is a chemical equation?
Question 2 Give an example of chemical equation?
Question 3 What is a balanced equation?
Question 4 What is an unbalanced equation?
Question 5 What are the steps of balancing the equation?
The method of representing a chemical reaction with the help of symbols and formula is called chemical equation.
For Example :
Zinc + Sulphuric acid → Zinc Sulphate + Hydrogen
The reactants are always written on left hand side in an equation with a plus sign between the.
The products are always written on right hand side in an equation with a plus sign between them.
A chemical equation is the short hand method of representing chemical reaction.
Balanced Equation: It has equal number of atoms of different elements in reactants and products.
Unbalanced Equation: It has unequal number of atoms of different elements in reactants and products.
H2 + O2 → H2O
Balancing of Chemical Equation
The process of making the number of different types of atoms equal on both side of an equation is called balancing equation.
Steps to balance chemical equation
(1) Write down the chemical reaction in the form of word equation, keeping reactants on left hand side and products on right hand side.
(2) Write symbol and formula of all reactants and products in word equation.
(3) Balance the equation by multiplying the symbols and formula by smallest possible figures.
(4) Make the equation informative by indicating physical state, heat changes, reaction condition.
(5) Indicate the physical state of reactant and products in an equation. We use the symbols as: solid(s), liquid(l), gas(g).
Example of balancing the equation
(1) CH4 +O2 → CO2 +H2O
Step 1) Make H atoms equal(Multiply products by 2)
CH4 +O2 → CO2 +2H2O
Step 2) Multiply oxygen of reactants by 2
CH4 + 2O2 → CO2 +2 H2O Balanced equation
(2) (Cu)2SO4 + NaOH → Cu(OH)2+Na2SO4
Step 1) Multiply sodium hydroxide by 2
CuSO4 + 2 NaOH → Cu(OH)2 + Na2SO4 Balanced equation
(3) Fe + H2O → Fe3O4 + H2
Step 1) Multiply Fe by 3 on left hand side
3 Fe+ H2O → Fe3O4 + H2
Step 2)Multiply oxygen by 4 on left hand side
3 Fe+ 4 H2O → Fe3O4 + H2
Step 3)Multiply hydrogen by 4 on right hand side
3 Fe+ 4 H2O → Fe3O4 +4 H2 Balanced equation
Other Notes from Chapter 1 Chemical Reaction and Equation
- Chemical Reaction and Equation
- Characteristics of Chemical reaction
- Combination reaction
- Decomposition reaction
- Displacement Reaction
- Double Displacement Reaction
- Oxidation and Reduction reaction
- Effects of oxidation Reaction in Everyday Life