Skip to content
ChemistryNEET 2025Valence bond and crystal field theory

Coordination Compounds

Which of the following are paramagnetic?

A. [NiCl4]2−\mathrm{[NiCl_4]^{2-}} · B. Ni(CO)4\mathrm{Ni(CO)_4} · C. [Ni(CN)4]2−\mathrm{[Ni(CN)_4]^{2-}} · D. [Ni(H2O)6]2+\mathrm{[Ni(H_2O)_6]^{2+}} · E. Ni(PPh3)4\mathrm{Ni(PPh_3)_4}

Choose the correct answer from the options given below:

  1. A.A and C only
  2. B.B and E only
  3. C.A and D only✓
  4. D.A, D and E only

Solution

[NiCl4]2−\mathrm{[NiCl_4]^{2-}} (Ni2+\mathrm{Ni^{2+}}, d8d^8, weak-field tetrahedral) has two unpaired electrons; so does [Ni(H2O)6]2+\mathrm{[Ni(H_2O)_6]^{2+}} (octahedral d8d^8). Ni(CO)4\mathrm{Ni(CO)_4} and Ni(PPh3)4\mathrm{Ni(PPh_3)_4} contain Ni(0), d10d^{10}; [Ni(CN)4]2−\mathrm{[Ni(CN)_4]^{2-}} is square planar d8d^8, all paired. Paramagnetic: A and D.

Save for spaced revision (free account)

More from this chapter in past papers

From Chemistry › Coordination Compounds › Valence bond and crystal field theory — lectures, notes and every past question on it.

Last revised . Found a mistake? Tell us — corrections are the fastest thing we act on.

ShareWhatsAppTelegram