Answer to Question #198267 in Chemistry for Cache

Question

How much energy is released during the combustion of 24.0 g of methane, CH4. DeltaH = -90 kJ/mol.

Answer 1

The combustion of methane undergoes according to the following reaction:

CH₄ + 2O₂ = CO₂ + 2H₂O

The number of moles of methane equals:

n(methane) = m(methane) / Mr(methane) = 24.0 g / 16.04 g/mol = 1.5 mol

From here, if 1 mol of methane releases 90 kJ, 1.5 mol of methane releases 1.5 mol × 90 kJ/mol = 135 kJ

Answer: 135 kJ