Determine Enthalpy Change

[Robertgc3]

Please help me answer and understand this:

Chloroform, CHCl3, is formed by the following reaction:

CH4(g) + 3 Cl2(g) → 3 HCl(g) + CHCl3 (g)

Determine the enthalpy change for this reaction (ΔH°rxn), using the following:

enthalpy of formation of CHCl3 (g), ΔH°f = – 103.1 kJ/mol

CH4(g) + 2 O2(g) → 2 H2O(l) + CO2(g) ΔH°rxn = – 890.4 kJ/mol

2 HCl (g) → H2 (g) + Cl2(g) ΔH°rxn = + 184.6 kJ/mol

C (graphite) + O2(g) → CO2(g) ΔH°rxn = – 393.5 kJ/mol

H2 (g) + ½ O2(g) → H2O(l) ΔH°rxn = – 285.8 kJ/mol



+ 145.4 kJ

– 305.3 kJ

– 145.4 kJ

+ 305.3 kJ

– 103.1 kJ