The combustion reaction of isopropyl alcohol is given below: C 3 H 7 O H (l) + 9 2 O 2 (g) → 3 C O 2 (g) + 4 H 2 O (g) The heat of combustion of isopropyl alcohol is - 2006 kJ/mol. Given the following information, calculate the heat of formation of isopropyl alcohol.

the heat of formation of isopropyl alcohol is - 317.82 kJ/mol

Explanation:

The heat of combustion of isopropyl alcohol is given as follows;

C₃H₇OH (l) + (9/2) O₂ → 3CO₂ (g) + 4H₂O (g)

The heat of combustion of CO₂ and H₂O are given as follows

C (s) + O₂ (g) → CO₂ (g) = - 393.50 kJ

H₂ (g) + 1/2·O₂ (g) → H₂O (l) = - 285.83 kJ

Therefore we have

3CO₂ (g) + 4H₂O (g) → C₃H₇OH (l) + (9/2) O₂ which we can write as

3C (s) + 3O₂ (g) → 3CO₂ (g) = - 393.50 kJ * 3 =

4H₂ (g) + 2·O₂ (g) → 4H₂O (l) = - 285.83 kJ * 4

3CO₂ (g) + 4H₂O (g) → C₃H₇OH (l) + (9/2) O₂ = + 2006 kJ/mol

-1180.5 - 1143.32 + 2006 = - 317.82 kJ/mol

Therefore, the heat of formation of isopropyl alcohol = - 317.82 kJ/mol.