For octahedral Mn (II) and tetrahedral Ni (II) complexes,
Question:

For octahedral $\mathrm{Mn}$ (II) and tetrahedral $\mathrm{Ni}$ (II) complexes, consider the following statements :

(I) both the complexes can be high spin.

(II) $\mathrm{Ni}$ (II) complex can very rarely below spin.

(III) with strong field ligands, Mn(II) complexes can be low spin.

(IV) aqueous solution of $\mathrm{Mn}$ (II) ions is yellow in color.

The correct statements are :

1. (I) and (II) only

2. (I), (III) and (IV) only

3. (I), (II) and (III) only

4. (II), (III) and (IV) only

Correct Option: , 3

Solution:

With weak field ligands $\mathrm{Mn}$ (II) will be of high spin and with strong field ligands it will be of low spin. $\mathrm{Ni}$ (II) tetrahedral complexes will be generally of high spin due to $s p^{3}$ hybridisation. Mn(II) is of light pink colour in aqueous solution.