Question

The incorrect statement is :

• A. In manganate and permanganate ions, the $\pi$ -bonding takes place by overlap of p-orbitals of oxygen and d-orbitals of manganese
• B. Manganate ion is green in colour and permanganate ion in purple in colour
• C. Manganate and permanganate ions are paramagnetic
• D. Manganate and permanganate ions are tetrahedral

Answer 1

Answer: (C)

Option 1 ) Manganate $\Rightarrow MnO _{4}^{2-}$,

Permanganate $\Rightarrow MnO _{4}^{-}$



After excitation



$2 \times 2p_{\pi} - 3d_{\pi\sigma}$



$2 \times 2 P_{\pi}-3 d_{\pi}$

$1 \times 2 P_{\pi}-4 P_{\pi}$

(2) $MnO _{4}^{2-} \Rightarrow $ green

$MnO _{4} \Rightarrow $ purple/violet

3) Manganate contains 1 unpaired electron hence it is paramagnetic

where as permanganetic contains no unpaired electrons hence it is diamagnetic

4) Both have $d ^{3} s$ hybridisation hence both have tetrahedral geometry