Discussion Forum



1)

 For the reaction ,

 $N_{2}(g)+3H_{2}\rightarrow2NH_{3}(g) ; \triangle H$ is equal to


A) $\triangle U+2RT$

B) $\triangle U-RT$

C) $\triangle U-2RT$

D) $\triangle U+RT$

Answer:

Option C

Explanation:

 For the reaction,

$N_{2}(g)+3H_{2}$ $\rightarrow$ $2NH_{3}(g) $

 $\triangle$ H is equal to $\triangle$ U=-2RT

$\because$      $\triangle H= \triangle U+ \triangle  nRT $

 For the given reaction,

$\triangle$ n , is the difference between the number of moles of product and the number of moles of reactants.

 $\triangle$ n= (2-4) =-2

 Hence, $\triangle H= \triangle U-2RT $