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Four successive members of the first row transition elements are listed below with atomic numbers. Which one of them is expected to have to highest E M 3 + / M 2 + o , value?

Options

  1. AF e Z = 26
  2. BM n Z = 25
  3. CC r Z = 24
  4. DC o Z = 27

Correct answer

D. C o Z = 27

Step-by-step solution

E C r 3 + / C r 2 + o = - 0.41 V ; E M n 3 + / M n 2 + o = + 1.57 V ; E F e 3 + / F e 2 + o = + 0.77 V ; E C o 3 + / C o 2 + o = + 1.97 V Standard reduction potential (SRP) value normally increases from left to right in the period of d-block elements. Some SRP values are exceptionally higher due to stability of the product ion. For e.g., E M n 3 + / M n 2 + o = + 1.57 V ; E C o 3 + / C o 2 + o = + 1.97 V .

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