Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETChemistryd 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).

Practice d and f Block Elements on Quantrex Academy →

More from d and f Block Elements

Although +3 oxidation state is most common in lanthanoids, cerium still shows +4 oxidation state because : 2026The lanthanide ion having four unpaired electrons is (Given : Atomic numbers of Ce =58 , Nd =60 , Tb =65 and Ho =67 ) 2026The green paramagnetic species formed by heating KMn O₄ at 513 K is 2026The calculated 'spin-only' magnetic moment of Ti ²⁺ (3d^2) is : 2026Match List I with List II : List I (Transition metal/compound/complex) List II (Catalytic Role) A. V ₂ O ₅ I. Preparation of ammonia from N ₂/ H ₂ mixture B. Fe II. Polymerisation 2026Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R . Assertion A : Generally, 3d transition metals have high melting points. Reas 2026Given below are two statements : Statement I : Ferromagnetism is considered as an extreme form of paramagnetism. Statement II : The number of unpaired electrons in a Cr ²⁺ ion ( Z 2025Which of the following set of ions act as oxidising agents? 2024 Full d and f Block Elements list All NEET PYQs