Determine the actual molar and mass oxygenfuel ratios- the

Question

The combustion of an unknown amount of ethylene (x moles of C₂H₄) in pure oxygen in a laboratory experiment produces the following dry exhaust gas analysis on a molar basis: 84.75% CO₂ and 15.25% O₂. Determine

a. The actual molar and mass oxygen/fuel ratios.

b. The percent of excess oxygen used.

c. The molar percentage of water vapor in the exhaust gas before it was dried for this analysis.