Question

For octahedral Mn(ll) and tetrahedral Ni(ll) complexes, consider the following statements:
(l) Both the complexes can be high spin.
(ll) Ni(ll) complex can very rarely be of low spin.
(lll) With strong field ligands, Mn(ll) complexes can be low spin.
(lV) Aqueous solution of Mn(ll) ions is yellow in color.
The correct statements are:

• A. (l), (ll) and (lll) only
• B. (l), (lll) and (lV) only
• C. (l) and (ll) only
• D. (ll), (lll) and (lV) only

Answer 1

The correct option is A (l), (ll) and (lll) only

With weak field ligands Mn(II) will be of high spin and with strong field ligands it will be of low spin. Ni(II) tetrahedral complexes will be generally of high spin due to $s{p}^3$ hybridisation.
Aqueous solution of Mn(II) ions is light pink in color.
Hence, (I), (II) and (III) are correct.