O2(g)

Practice Questions (2)

• The enthalpy of change for the reaction H2(g) + 1/2 O2(g) → H2O (g) is -71.2 kJ/mol. The enthalpy of change for the reaction C2H2(g) + 2H2(g) → C2H6(g) is -94.5 kJ/mol. The enthalpy of change for the reaction C2H6(g) + 7/2 O2(g) → 2CO2(g) + 3H2O(g) is -283 kJ/mol. What is the enthalpy of change for the reaction 4CO2(g) + 2H2O(g) → 2C2H2(g) + 5O2(g)?

• What is the enthalpy change for the reaction: C2H2(g) + 5/2O2(g) → 2CO2(g) + H2O(g) given the following chemical equations: (1) C2H2(g) + 5/2O2(g) → 2CO(g) + H2O(g) ΔH = -636.1 kJ/mol; (2) CO(g) + 1/2O2(g) → CO2(g) ΔH = -283.0 kJ/mol; (3) C2H2(g) + 5/2O2(g) → 2CO2(g) + H2O(g) ΔH = -1299.5 kJ/mol?