Question

Consider the Daniell cell: \[ Zn|Zn^{2+} \;||\; Cu^{2+}|Cu \] and identify the incorrect statement:

• A. Zinc acts as the anode
• B. Copper undergoes oxidation
• C. Sulphate ions migrate to maintain charge balance
• D. EMF depends on electrolyte concentration

Hint:

In Daniell cell: Zn is always anode (oxidation), Cu is cathode (reduction).

Answer 1

The Correct Option is B

Concept: In Daniell cell: \[ Zn \rightarrow Zn^{2+} + 2e^- \quad (\text{oxidation at anode}) \] \[ Cu^{2+} + 2e^- \rightarrow Cu \quad (\text{reduction at cathode}) \]

Step 1: Identify anode and cathode.
- Zinc loses electrons → oxidation → anode - Copper gains electrons → reduction → cathode

Step 2: Check each statement.
(A) Zinc acts as anode → TRUE (B) Copper undergoes oxidation → FALSE (it undergoes reduction) (C) Ions migrate for charge balance → TRUE (D) EMF depends on concentration (Nernst equation) → TRUE Final Answer: \[ \text{Incorrect statement is (B)} \]