Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
MHT CET202615 April 2026Evening ShiftChemistryd and f Block ElementsActual

Which of the following elements in +3 oxidation state forms colourless compounds?

Options

  1. ASc
  2. BNi
  3. CCr
  4. DV

Correct answer

A. Sc

Step-by-step solution

The atomic number of Sc is 21 . The electronic configuration of Sc is [ Ar ] 3d¹ 4s² . In the +3 oxidation state, the electronic configuration of Sc ³⁺ is [ Ar ] 3d⁰ 4s⁰ . Since there are no unpaired electrons in the d -orbital of Sc ³⁺ , d-d transitions are not possible. Therefore, Sc ³⁺ forms colourless compounds. Answer: Sc

Practice d and f Block Elements on Quantrex Academy →

More from d and f Block Elements

Pick out the correct option Assertion(A): Mercury is not considered as a transition element Reason (R): Mercury is a liquid 2026Which of the following does not correctly represent the order of the property indicated against it? 2026The element with the highest third ionisation enthalpy is: 2026The product and its colour when MnO₂ is fused with KOH in presence of O₂ : 2026The ion that has a spin only magnetic moment of 5.9 BM is: 2026Which one of the following species will impart colour to an aqueous solution? 2026The basic character of transition metal monoxides follows the order: 2026K ₂ Cr ₂ O ₇ on heating with aqueous NaOH gives ------------------------- 2026 Full d and f Block Elements list All MHT CET PYQs