UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper I
Q7(b). Nickel–cobalt displacement
Question
The standard reduction potentials of the Ni²⁺/Ni and Co²⁺/Co couples are -0.25 V and -0.277 V respectively. Comment on the feasibility of the following reaction at 298 K: Ni²⁺ + Co ⇌ Ni + Co²⁺.
Answer in brief
The forward reaction is favourable under standard conditions, but only modestly: E°=+0.027 V and K≈8.18.
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CoversNickel–cobalt displacementElectrochemical feasibility
All parts of Question 7
- 7(a) Cerimetric titration of iron15 marks
- 7(b) Nickel–cobalt displacement15 marks