Final answer:
To calculate the moles of ethanol, the mass or volume and the molar mass of ethanol are required. As the question lacks specific details, we cannot determine the correct option from A, B, C, or D without additional data.
Step-by-step explanation:
To calculate the moles of ethanol used in the combustion, we must first know the mass or volume of ethanol we're starting with and its corresponding molar mass. The molar mass of ethanol (C2H5OH) is 46.07 g/mol, which is necessary to convert the mass or volume of ethanol to moles.
For example, if we have 31.6 g of ethanol and use its molar mass, we can calculate the moles of ethanol. The formula to calculate moles is:
moles of ethanol = mass of ethanol / molar mass of ethanol
Using the given example:
moles of ethanol = 31.6 g / 46.07 g/mol
moles of ethanol = 0.686 moles
However, since the question does not provide specific details on the mass or volume of ethanol used, we cannot select from options A, B, C, or D without additional information.