Question

For octahedral Mn(II) and tetrahedral Ni(II) complexes, consider the following statements:

1. Both the complexes can be high spin.
2. Ni(II) complex can very rarely below spin.
3. With strong field Ligands, Mn(II) complexes can be low spin.
4. Aqueous solution of Mn (II) ions is yellow in colour.

The correct statements are:

Options

• (i) and (ii) only

• (i), (ii) and (iii) only

• (i), (iii) and (iv) only

• (ii), (iii) and (iv) only

Answer 1

(i), (ii) and (iii) only

Explanation:

Mn(II) forms a high spin (or spin free) complex in the presence of a weak field ligand but a low spin complex in the presence of a strong field ligand. Td complexes of Ni(II) are high spin complexes with sp³ hybridised orbitals. Mn(II) ion aqueous solution is generally colourless.