According to the standard reduction potentials:
Pb²⁺(aq) + 2e– → Pb(s) E˚ = –0.13 V
Fe²⁺(aq) + 2e– → Fe(s) E˚ = –0.44 V
Zn²⁺(aq) + 2e– → Zn(s) E˚ = –0.76 V
Which species will reduce Mn³⁺ to Mn²⁺ [E˚ = 1.51 V] but will NOT reduce Cr³⁺ to Cr²⁺ [E˚ = –0.40 V]?

Question

According to the standard reduction potentials:
Pb2+(aq)  + 2e– → Pb(s) E˚ = –0.13 V
Fe2+(aq) + 2e– → Fe(s) E˚ = –0.44 V
Zn2+(aq) + 2e– → Zn(s) E˚ = –0.76  V
Which species will reduce Mn3+ to Mn2+ [E˚ = 1.51 V] but will NOT reduce Cr3+ to Cr2+ [E˚ = –0.40 V]?

Accepted Answer

Correct answer: A.

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