Question

$H_2\left(g\right)+I_2\left(g\right)⟶2HI\left(g\right)$

For this reaction, relate $\Delta H$ and $\Delta U$.

• A. $\Delta H$ =$\Delta U$
• B. $\Delta H$ > $\Delta U$
• C. $\Delta H$ < $\Delta U$
• D. None of these

Answer 1

Answer: (A)

$\Delta H$ =$\Delta U$

As we know,
$\Delta H$ =$\Delta U+\Delta n_{g}RT$
here,
$H_2\left(g\right)+I_2\left(g\right)⟶2HI\left(g\right)$
$\Delta n_g=0$
so,
$\Delta H$ =$\Delta U$