8. Thermochemistry
Hess's Law
8. Thermochemistry Hess's Law
30PRACTICE PROBLEM
Calculate ΔHrxn for the reaction:
CH4(g) + 4 F2(g) → CF4(g) + 4 HF( g)
Use the following reactions and given ΔH's:
C(s) + 2 H2(g) → CH4(g) ΔH = -74.6 kJ
C(s) + 2 F2(g) → CF4(g) ΔH = -933 kJ
H2(g) + F2(g) → 2 HF(g) ΔH = -542 kJ
Calculate ΔHrxn for the reaction:
CH4(g) + 4 F2(g) → CF4(g) + 4 HF( g)
Use the following reactions and given ΔH's:
C(s) + 2 H2(g) → CH4(g) ΔH = -74.6 kJ
C(s) + 2 F2(g) → CF4(g) ΔH = -933 kJ
H2(g) + F2(g) → 2 HF(g) ΔH = -542 kJ