question_answer

Standard entropies of \[{{X}_{2}},{{Y}_{2}}\] and \[X{{Y}_{3}}\] are 60, 40 and \[50\,J\,{{K}^{-1}}\,mo{{l}^{-1}}\] respectively. For the reaction \[\frac{1}{2}{{X}_{2}}+\frac{3}{2}{{Y}_{2}}X{{Y}_{3}};\Delta H=-30kJ,\] to be at equilibrium, the temperature should be                                                                                 [AIPMT (S) 2010]

A)  750 K              

B)       1000 K

C)  1250 K            

D)       500 K

Correct Answer: A

Solution :

For the reaction,

We know that,

At equilibrium,