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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 : [CoCl(NH3)5]2+ absorbs at lower wavelength of light with respect to [Co(NH3)5(H2O)]3+. Reason R : It is because the wavelength of the light absorbed depends on the oxidation state of the metal ion. In the light of the above statements, choose the correct answer from the options given below :

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

Correct answer: (1) A is false but R is true

Solution

The assertion is incorrect because the absorption of light at lower wavelengths is influenced by the ligand field strength and not solely by the oxidation state of the metal ion. The reason is true as the oxidation state can affect the electronic transitions, but it does not correctly explain the assertion.

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