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99 Percentile Qs Bank for JEE MainChemistryd and f Block Elements

Choose the correct option regarding the following. Assertion Actinides exhibit a larger number of oxidation states than lanthanides. Reason There is a large energy gap between 5 f, 6 d and 7 s sub-shells.

Options

  1. AAssertion and Reason are correct, and Reason is the correct explanation for the Assertion.
  2. BAssertion and Reason are correct, and Reason is not the correct explanation for the Assertion.
  3. CAssertion is correct, Reason is wrong.
  4. DAssertion is incorrect, Reason is correct.

Correct answer

C. Assertion is correct, Reason is wrong.

Step-by-step solution

Actinides exhibit larger oxidation states than lanthanides because of the very small energy gap between 5 f, 6 d and 7 s subshells. Thus, the outermost electrons get easily excited to the higher energy levels, giving variable oxidation states. Hence, Assertion is correct, Reason is incorrect. Thus, the correct option is (3).

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