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Indian Forest Service (Mains)

Chemistry optional

  • 2 papers
  • 200 marks each
  • 3 h per paper

Paper I covers physical and inorganic chemistry.

Indian Forest Service (Mains), Chemistry optional · 2023 · Paper I

Q4(c). Cell voltage under load and electrolysis

Question

(i) The following cell has a resistance of 5.00 Ω. Calculate its potential when producing a current of 0.100 A: Cd|Cd²⁺(0.0100 M)‖Cu²⁺(0.0100 M)|Cu. Given ECu = 0.278 V and ECd = −0.462 V. (ii) Calculate the potential required to generate a current of 0.100 A in the reverse direction, using the same electrode potentials and resistance. (5+5 marks)

Answer in brief

The discharge terminal voltage is 0.240 V. Reversing the current at the same magnitude requires an opposing applied voltage of 1.240 V, neglecting overpotentials.

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CoversIR dropcell potentialelectrolytic cellgalvanic cellCd–Cu celloverpotential

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