Calcium carbide is used for the artificial ripening of fruits. Actually the fruit ripens because of the heat evolved while calcium carbide reacts with moisture. During this reaction calcium hydroxide and acetylene gas is formed. If 200 cm³ of acetylene is formed from a certain mass of calcium carbide, find the volume of oxygen required and carbon dioxide formed during the complete combustion. The combustion reaction can be represented as below.

2C₂H₂(g) + 5O₂(g) ⟶4CO₂(g) + 2H₂O(g)

$\begin{matrix} 2\text{C}$2\text{H}2 & + & 5\text{O}2 \longrightarrow & 4\text{CO}2 & + &2\text{H}_2\text{O} \ 2\text{ mol.} & & 5 \text{ mol.} & 4\text{ mol.}\ \end {matrix} According to Gay-Lussac's law,

2 volume of acetylene requires 5 volume of oxygen

1 volume of acetylene requires $\dfrac{5}{2}$ = 2.5 volume of oxygen

∴ 200 cm³ of acetylene requires $\dfrac{2.5}{1}$ x 200

= 500 cm³ of oxygen

2 volume of acetylene produces 4 volume of CO₂

1 volume of acetylene produces $\dfrac{4}{2}$ = 2 volume of CO₂

∴ 200 cm³ produces $\dfrac{2}{1}$ x 200 = 400 cm³ of CO₂