Which one of the following reactions does not take place?

Step-by-step solution

The reaction, Br ₂+2 Cl ⁻ 2 Br ⁻+ Cl ₂ does not take place as the E_ red ^ of the above reaction is comes out to be negative. Thus, the reaction is non-spontaneous. Half cell reaction are given as At cathode, Br ₂+2 e⁻ 2 Br ⁻ ; E_ Br ₂ / Br ⁻ ^ =1.09 ~V At anode, 2 Cl ⁻ Cl ₂+2 e⁻ ; E_ Cl ₂ / Cl ⁻ ^ =1.36 ~V E_ red ^ =E_ cathode ^ -E_ anode ^ (1.09-1.36) V -0.27 ~V But the E_ red ^ values of other reaction are comes out to be positive. Thus, the all other reaction can take place.