What volume of oxygen is required to burn completely a mixture of 22.4dm3 of methane and 11.2dm3 of hydrogen into carbon dioxide and steam?
1 vol of methane requires 2 vol of oxygen.
22.4dm3 of methane requires 2×22.4dm3 oxygen.
22.4dm3 of methane requires 44.8dm3 oxygen.
2 vol of hydrogen requires 1 vol of oxygen.
11.2dm3 of hydrogen requires 5.6dm3 of oxygen.
Total oxygen required = (44.8+5.6)dm3 = 50.4dm3