BITSAT2019ChemistryThermodynamics (C)Actual
The heat of reaction for C 10 H 8 s + 12 O 2 g ⟶ 10 CO 2 g + 4 H 2 O ( l ) at constant volume is - 1228 . 2 kcal at 25 0 C . The heat of reaction at constant pressure and same temperature is
Options
- A- 1228 . 2   kcal
- B- 1229 . 3   kcal
- C- 1232 . 9   kcal
- D- 1242 . 6   kcal
Correct answer
B. - 1229 . 3   kcal
Step-by-step solution
Heat of reaction at constant pressure is represented by ΔH Heat of reaction at constant volume is represented by ΔU C 10 H 8 s + 12 O 2 g ⟶ 10 CO 2 g + 4 H 2 O We known that ΔH = ΔE + Δn g RT Δn g = 10 - 12 = - 2 ΔH = - 1228 . 2 × 10 3 + - 2 × 2 × 298 = - 1229393   Cal = - 1229 . 39   kcal