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NEET CHEMISTRYThe d-and f-Block ElementsMedium

Question

Actinoids exhibit more number of oxidation states than lanthanoids. It is because of:

A

The greater metallic character of the lanthanoids than that of the corresponding actinoids.

B

More energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals.

C

The lesser energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals.

D

More active nature of the actinoids.

Step-by-Step Solution

According to NCERT (Section 4.6.3), actinoids exhibit a greater range of oxidation states (e.g., +3, +4, +5, +6, +7) compared to lanthanoids (which are predominantly +3). This is attributed to the fact that the 5f, 6d, and 7s energy levels are of comparable energies in actinoids. This implies that the energy difference between 5f and 6d orbitals is small (lesser), allowing electrons from both subshells to participate in bonding. In contrast, in lanthanoids, the 4f orbitals are relatively buried and have a larger energy gap with the 5d orbitals, restricting the number of oxidation states available.

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from The d-and f-Block Elements. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYThe d-and f-Block Elementsactinoidsexhibitnumberoxidationstates

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