The chemical formula of ethanol is C₂H₆O. It burns in the presence of excess oxygen to form CO₂ and H₂O. How many grams of H₂O are produced from the combustion of 25.0 g of ethanol?

Question

Quizplus · Accepted Answer

The balanced chemical equation for the combustion of ethanol is C2H6O + 3O2 → 2CO2 + 3H2O. The molar mass of ethanol (C2H6O) is 46.08 g/mol. From 25.0 g of ethanol, moles of ethanol = 25.0 g / 46.08 g/mol = 0.542 mol. According to the equation, 1 mol of ethanol produces 3 mol of H2O. Therefore, 0.542 mol of ethanol produces 0.542 * 3 = 1.626 mol of H2O. The molar mass of H2O is 18.02 g/mol, so the mass of H2O produced is 1.626 mol * 18.02 g/mol = 29.3 g.

The Chemical Formula of Ethanol Is C2H6O

The Chemical Formula of Ethanol Is C₂H₆O