Question

For the reaction $H_2(g) + I_2(g) \to 2HI (g)$ the change in enthalpy ($\Delta H$) will be

• A. $= \Delta\,E$
• B. $>\,\Delta\,E$
• C. $< \,\Delta\,E$
• D. either (b) or (c)

Answer 1

Answer: (A)

$= \Delta\,E$

Answer 2

$H _{2}(g)+ I _{2}(g) \rightarrow 2 Hl (g)$ $\Delta n=$ no. of product speices - no. of reactant spccies $=2-(1+1)=0$ As $\Delta H=\Delta E+\Delta n R T$ $\Rightarrow \Delta H=\Delta E+0 \times R T$ $\Rightarrow \Delta H=\Delta E$