The relation between heat at constant pressure (\( \Delta H \)) and at constant volume (\( \Delta U \)) is:
\( \Delta H = \Delta U + \Delta n_g RT \)
For benzoic acid:
\( C_6H_5COOH(s) + \frac{15}{2} O_2(g) \rightarrow 7CO_2(g) + 3H_2O(l) \)
\( \Delta n_g = 7 - \frac{15}{2} = -\frac{1}{2} \). Substituting:
\( \Delta H = -321.30 - \frac{1}{2} R \times 300 \)
Here, \( R \approx 8.314 \, \text{J/mol.K} \). Solving gives:
\( x = 150 \)
List-I | List-II | ||
(A) | Isothermal process | (I) | No heat exchange |
(B) | Isochoric process | (II) | Carried out at constant temperature |
(C) | Isobaric process | (III) | Carried out at constant volume |
(D) | Adiabatic process | (IV) | Carried out at constant pressure |