question_answer

The enthalpy and entropy change for the reaction: \[B{{r}_{2}}(l)+C{{l}_{2}}(g)\to 2BrCl(g)\] are \[30\,\,kJ\,\,mo{{l}^{-1}}\] and \[105\,\,k{{J}^{-1}}\,\,mo{{l}^{-1}}\] respectively. The temperature at which the reaction will be in equilibrium is:                                                                                                                                     [AIPMT (S) 2006]

A)  285.7 K             

B)  273 K

C)  450 K    

D)          300 K

Correct Answer: A

Solution :

           

At equilibrium Gibbs free energy change  is equal to zero. The following thermodynamic relation is used to show the relation of  with enthalpy change and entropy change