JEE PYQ: Electrochemistry Question 15
Question 15 - 2020 (04 Sep Shift 1)
Identify the incorrect statement from the options below for a Daniell cell with $E^0_{\text{Cu}^{2+}|\text{Cu}} = +0.34$ V; $E^0_{\text{Zn}^{2+}|\text{Zn}} = -0.76$ V:
(1) If $E_{\text{ext}} > 1.1$ V, $e^-$ flows from Cu to Zn
(2) If $E_{\text{ext}} > 1.1$ V, Zn dissolves at Zn electrode and Cu deposits at Cu electrode
(3) If $E_{\text{ext}} < 1.1$ V, Zn dissolves at anode and Cu deposits at cathode
(4) If $E_{\text{ext}} = 1.1$ V, no flow of $e^-$ or current occurs
Show Answer
Answer: (2) If $E_{\text{ext}} > 1.1$ V, Zn dissolves at Zn electrode and Cu deposits at Cu electrode
Solution
When $E_{\text{ext}} > 1.1$ V, the cell acts as electrolytic cell. Cu dissolves at anode and Zn deposits at cathode. So option (2) is incorrect.
BETA
