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Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The spin only magnetic moment value for [Fe(CN)6]3- is 1.74 BM, whereas for [Fe(H2O)6]3+ is 5.92 BM. Reason B: In both complexes, Fe is present in +3 oxidation state. In the light of the above statements, choose the correct answer from the options given below: (1) A is false but R is true (2) A is true but R is false (3) Both A and R are true but R is NOT the correct explanation of A (4) Both A and R are true and R is the correct explanation of A

1. A is false but R is true
2. A is true but R is false
3. Both A and R are true but R is NOT the correct explanation of A
4. Both A and R are true and R is the correct explanation of A

Correct answer: Both A and R are true but R is NOT the correct explanation of A

Solution

Assertion A correctly states the magnetic moment values for the two complexes, reflecting their differing ligand fields. Reason R is also true, as both complexes have iron in the +3 oxidation state, but it does not explain why their magnetic moments differ due to the influence of the ligands on the electron configuration.

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