Question

How many mol of potassium chlorate is to be heated to produce 5.6 litres of oxygen at $0{}^{\circ }\text{C}$ and 1 atm?

Answer 1

$\begin{array}{cccc}& 2KCl{O}_3& \to 2KCl& +3O_2\\ \text{Mol ratio for reaction:}& 2\text{mol}& 2\text{mol}& 3\text{mol}\end{array}$

$\because 3\times 22.4$ litre $O_2$ is formed by 2 mol of $KCl{O}_3$.
$\therefore$ 5.6 litres $O_2$ is formed by $=\frac{2\times 5.6}{3\times 22.4}=\frac{1}{6}\approx 0.17$ mol of $KCl{O}_3$