કઈ પ્રક્રિયા માટે $\Delta H \neq \Delta U$ થાય?

• A
  $H_{2(g)} + I_{2(g)} \longrightarrow 2 HI_{(g)}$
• B
  $2 NO_{(g)} \longrightarrow N_{2(g)} + O_{2(g)}$
• C
  $N_{2(g)} + 3 H_{2(g)} \longrightarrow 2 NH_{3(g)}$
• D
  $C_{(s)} + O_{2(g)} \longrightarrow CO_{2(g)}$