29. Consider the following chemical equations and their enthalpy changes.

Question

CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) ΔH = −8.0 × 102 kJ
CaO(s) + H2O(_) → Ca(OH)2(aq) ΔH = −65 kJ
What volume of methane, at 20°C and 100 kPa, would have to be combusted in order to release the same amount of energy as the reaction of 1.0 × 102 g of CaO with sufficient water? (The volume of 1.00 mol of any gas at 20°C and 100 kPa is 24 L.)

i tried solving this question, i found the amount of energy it takes for the CaO and found the grams needed for methane to produce such energy, i get 2.3g but than how do i convert it to litres is confusing.... please help.

Answer 1

Can't you use PV = nRT?