Question
Chemistry Question on Structure of atom
The enthalpy and entropy change for the reaction:Br2(l)+Cl2( g)→2BrCl(g) are 30kJmol−1 and 105JK−1mol−1 respectively.The temperature at which the reaction will be in equilibrium is:
A
(A) 273K
B
(B) 450K
C
(C) 300K
D
(D) 285.7K
Answer
(D) 285.7K
Explanation
Solution
Explanation:
At equilibrium, Gibbs free energy change (ΔG∘) is equal to zero. The following thermodynamic relation is used to show the relation of (ΔG∘) with the enthalpy change (ΔH∘) and entropy change (ΔS∘).ΔG∘=ΔHo−ΔSo0=30×103( J mol−1)−T×105( J K−1)mol−1Therefore, T=30×103105 K=285.71 KHence, the correct option is (D).