Potassium chlorate is heated with a little manganese dioxide: $2\,\text{KClO}_3 \rightarrow 2\,\text{KCl} + 3\,\text{O}_2$. The oxygen from $0.490\ \text{g}$ of $\text{KClO}_3$ is collected over water at $300\ \text{K}$, at a total pressure of $1.00\ \text{atm}$. The vapour pressure of water at this temperature is $0.036\ \text{atm}$. Take $R = 0.0821\ \text{L atm K}^{-1}\ \text{mol}^{-1}$. What volume of moist gas is collected? Atomic masses in $\text{g mol}^{-1}$: O 16.0, K 39.0, Cl 35.5.