Question

Based on the following reaction, determine how much heat is released if 500. grams of methane is combusted in excess oxygen: CH4 + 2 O2  CO2 + 2 H2O H= – 890 kJ

Answer 1

Answer:

- 13,150.6kJ

Explanation:

CH4 + 2 O2 ------> CO2 + 2 H2O ΔH= – 890 kJ

The ΔH is enthalpy change of combustion , which is the heat is either absorbed or released by the combustion of one mole of a substance.

ΔH=−890 kJ/mol (released in the combustion of one mole of methane)

using the molar mass  (in grams )of methane to get moles of sample

(237g × 1 mole of CH4)/16.04g=14.776 moles  of CH4

Since 1 mole produces 890 kJ of heat upon combustion, then 14.776 moles will produce

ΔH = 14.776moles of CH4 × 890kJ/1mole of CH4

=13,150.6kJ

Therefore ΔH = - 13,150.6kJ