Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETChemistryd and f Block Elements

Which of the following statements regarding the electronic configuration and redox behaviour of lanthanoid ions is incorrect?

Options

  1. AEu ²⁺ has a 4f⁷ configuration and acts as a strong reducing agent.
  2. BTb ⁴⁺ has a half-filled 4f⁷ configuration and acts as a strong reducing agent.
  3. CYb ²⁺ has a fully-filled 4f¹⁴ configuration and acts as a reducing agent.
  4. DCe ⁴⁺ has a noble gas configuration but acts as a strong oxidising agent.

Correct answer

B. Tb ⁴⁺ has a half-filled 4f⁷ configuration and acts as a strong reducing agent.

Step-by-step solution

The most stable oxidation state for lanthanoids is +3 . Ions in the +2 state tend to lose an electron to reach +3 , acting as reducing agents, while ions in the +4 state tend to gain an electron to reach +3 , acting as oxidising agents. Eu ²⁺ ( 4f⁷ ) and Yb ²⁺ ( 4f¹⁴ ) are in the +2 oxidation state and act as reducing agents to reach the +3 state. Ce ⁴⁺ (noble gas configuration) and Tb ⁴⁺ ( 4f⁷ ) are in the +4 oxidation state. Despite the stability of their respective electronic configurations, both act as strong o

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