Coke burns in a limited supply of air so that all of the oxygen forms carbon monoxide: 2C + O₂ →…

Coke burns in a limited supply of air so that all of the oxygen forms carbon monoxide: $2\text{C} + \text{O}_{2} \to 2\text{CO}$. Air is $21.0\%$ oxygen and $79.0\%$ nitrogen by volume, and nitrogen takes no part. Find the percentages by volume of carbon monoxide and nitrogen in the gas that leaves. Then find the heat released when the carbon monoxide in $1.00\ \text{m}^3$ of the gas burns to carbon dioxide, with $\Delta H = -283.0\ \text{kJ/mol}$ for CO, at $273\ \text{K}$ and $1\ \text{atm}$. Use $22.4\ \text{L/mol}$ and $1\ \text{m}^3 = 1000\ \text{L}$.