Which of the following relations between enthalpy change $(\Delta H)$ and internal energy change $(\Delta U)$ is correct for the given reactions?

• A
  $H_{2(g)} + I_{2(g)} \to 2HI_{(g)}$; $\Delta n_g = 0$,so $\Delta H = \Delta U$
• B
  $N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}$; $\Delta n_g = -2$,so $\Delta H < \Delta U$
• C
  $2SO_{3(g)} \to 2SO_{2(g)} + O_{2(g)}$; $\Delta n_g = +1$,so $\Delta H > \Delta U$
• D
  All of the above