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E Cu 2 + | Cu 0 = + 0 .34 V E Zn 2 + | Zn 0 = − 0 .76 V Identify the incorrect statement from the options below for the above cell:

Options

  1. AIf E ext > 1 .1   V ,   e – flow from Cu to Zn
  2. BIf E ext > 1 .1   V ,   Zn dissolves at Zn electrode and Cu deposits at Cu electrode
  3. CIf E ext < 1 .1   V ,   Zn dissolves at anode and Cu deposits at cathode
  4. DIf E ext = 1 .1   V , no flow of e – or current occurs

Correct answer

B. If E ext > 1 .1   V ,   Zn dissolves at Zn electrode and Cu deposits at Cu electrode

Step-by-step solution

E cell ∘ = E Cu 2 + Cu ∘ − E Zn 2 + Zn ∘ = 1 .1   V So If E = 1 .1   V no electron will flow At E > 1 . 1   V cell act as electrolytic cell and electron will flow from Cu to Zn . At E < 1 . 1   V cell act as electrochemical so Zn dissolve and Cu deposit.

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