(a) What is a chemical equation? Explain with the help of an example.
(b) Giving examples, state the difference between balanced and unbalanced chemical equations.
(c) Balance the following chemical equations:
(i) NH3 → N2+H2
(ii) C + CO2 → CO
Balanced Chemical Equation | Unbalanced Chemical Equation |
A balanced chemical equation has an equal numbers of atoms of different elements in the side of reactants and products. | An unbalanced chemical equation has an unequal number of atoms of one or more elements in the reaction. |
In a balanced chemical equation the sum of masses of the reactants is equal to the sum of the masses of the products. | In an unbalanced chemical equation the sum of masses of the reactants is not equal to the sum of the masses of the products. |
It obeys the law of conservation of mass | It does not obey the law of conservation of mass |
Example: Zn (s) + H2SO4 (aq) → ZnSO4 (aq) + H2 (g) Here, number of Zn, H, S and O are same in both reactants' and products' side. |
Example: H2 + O2 → H2O Here, one oxygen atom is more in reactant's side than in product's side; it means one atom of oxygen is being destroyed, which is a violation of law of conservation of mass. |