Question

Find the amount in kJ of heat exchanged by the combustion of 61.9 g of ethane (C2H6(8) given that the molar enthalpy of combustion of ethane is -1,451 kJ/mol. 3
or more sig figs

Answer 1

Answer:

2994 kJ

Explanation:

When one mol of ethane (C₂H₆) is combusted, 1451 kJ of heat is exchanged.

First we convert 61.9 g of C₂H₆ into moles, using its molar mass:

• 61.9 g ÷ 30 g/mol = 2.06 mol C₂H₆

Finally we calculate how much heat is exchanged by the combustion of 2.06 moles of C₂H₆:

• 2.06 mol * 1451 kJ/mol = 2994 kJ