[Co(H_2O)_6]^(2+) (aq) " (pink) " + 4Cl^(-) (aq) hArr [COCl_4]^(2-) (aq) "(blue)"+6H_2O (l) In the above reaction at equilibrium,the reaction mixture is blue in colour at room temperature. On cooling this mixture,it becomes pink in colour. On the basis of this information, which one of the following is true ?

[Co(H_2O)_6]^(2+) (aq) " (pink) " + 4Cl^(-) (aq) hArr [COCl_4]^(2-) (a

1.	[Co(H_2O)_6]^(2+) (aq) " (pink) " + 4Cl^(-) (aq) hArr [COCl_4]^(2-) (aq) "(blue)"+6H_2O (l) In the above reaction at equilibrium,the reaction mixture is blue in colour at room temperature. On cooling this mixture,it becomes pink in colour. On the basis of this information, which one of the following is true ?
Answer» `Delta gt 0` for the forward reaction `Delta H = 0` for the reverse reaction `Delta lt 0 ` for the forward reaction Sign of the `Delta H` cannot be PREDICTED based on this information. Solution :On COOLING, reverse reaction predominates and the solution is pink in colour. `:.` Decrease in temperature, favours the reverse reaction i.e., reverse reaction is exothermic `(DELTAH LTO)` and for the forward reaction is endothermic `(DeltaH gt 0)`.