Use the standard reduction potentials to determine what is observed at the cathode
Channel: Doubtnut
Date: 2020-04-19

Use the standard reduction potentials to determine what is observed at the cathode during the electrolysis of a 1.0 M solution of KBr that contains phenolphthalein.   `O_(2)(g) + 4H^(+)(aq) + 4e^(-) rightarrow 2H_(2)O(l)` `E^(@) = 1.23V`   `Br_(2)(l) + 2e^(-) rightarrow 2Br^(-)(aq)` `E^(@) = 1.07V`   `2H_(2)O(l) + 2e^(-) rightarrow H_(2)(g) + 2OH^(-)` `E^(@0 = -0.80V`   `K^(+) (aq) + e^(-) rightarrow K(s)` `E^(@) = -2.92V`