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Karnataka Board PUCPUC Science 2nd PUC Class 12

CuSOX4⋅5HX2O is blue in colour while CuSOX4 is colourless. Why?

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Question

\[\ce{CuSO4 . 5H2O}\] is blue in colour while \[\ce{CuSO4}\] is colourless. Why?

Short/Brief Note
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Solution

In \[\ce{CuSO4 . 5H2O}\], water acts as ligand as a result it causes crystal field splitting. Hence d–d transition is possible in \[\ce{CuSO4 . 5H2O}\] and shows colour. In the anhydrous \[\ce{CuSO4}\] due to the absence of water (ligand), crystal field splitting is not possible and hence no colour.

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Chapter 9: Coordination Compounds - Exercises [Page 124]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 9 Coordination Compounds
Exercises | Q III. 34. | Page 124

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Choose the correct answer from the options given below:


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