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Karnataka Board PUCPUC Science 2nd PUC Class 12

How would you account for the following: Cobalt (II) is stable in aqueous solutions, but in the presence of complexing reagents, it is easily oxidised.

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Question

How would you account for the following:

Cobalt (II) is stable in aqueous solutions, but in the presence of complexing reagents, it is easily oxidised.

Very Short Answer
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Solution

In the presence of complexing reagents, the crystal field stabilization energy is greater than the third ionization enthalpy of cobalt. Thus, Co (II) is easily oxidized to Co (III).

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Chapter 4: d-and ƒ-Block Elements - 'NCERT TEXT-BOOK, Exercises [Page 507]

APPEARS IN

Nootan Chemistry [English] Class 12 ISC
Chapter 4 d-and ƒ-Block Elements
'NCERT TEXT-BOOK, Exercises | Q 8.21 (ii) | Page 507
NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 4 The d-block and f-block Elements
Exercises | Q 4.21 (ii) | Page 116

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