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NEET 2018 · ChemistryPrevious Year Question

Which one of the following elements is unable to form ion?

Answer: (A) . \textbf{Answer:} (A) \textbf{Solution:} Boron has no vacant d-orbitals in its valence shell, so it cannot expand its covalency beyond 4 (cannot expand its octet).

  1. A.✓
  2. B.
  3. C.
  4. D.

Correct Answer

(A)

Solution & Explanation

\textbf{Answer:} (A) \textbf{Solution:} Boron has no vacant d-orbitals in its valence shell, so it cannot expand its covalency beyond 4 (cannot expand its octet). Hence it cannot form an octahedral ion, unlike , and which have accessible d-orbitals.

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