Question

The combustion of ethane produces carbon dioxide and water. If 27.6 g C2H6 are burned in the presence of excess air (O2) and 76.7 g of carbon dioxide are produced, what is the percent yield?

Answer 1

2 C2H6 + 7 02 --> 4 CO2 + 6 H20

divide by molar mass to find moles of ethane
... 27.6 / molar mass

find expected moles of CO2 ... twice ethane
... use molar mass to find expected yield

% yield = 76.7 / expected yield