Question

LIST-I contains metal species and LIST-II contains their properties.

LIST I		LIST II
1	${\left[Cr(CN{)}_6\right]}^{4-}$	P	$t_{2g}$ orbitals contain 4 electrons
2	${\left[RuC{l}_6\right]}^{2-}$	Q	$\mu ($ spin-only $)=4.9BM$
3	${\left[Cr{\left(H_{2}O\right)}_6\right]}^{2+}$	R	low spin complex ion
4	${\left[Fe{\left(H_{2}O\right)}_6\right]}^{2+}$	S	metal ion in $4+$ oxidation state
		v	$d^4$ species

[Given : Atomic number of $Cr=24,Ru=44,Fe=26$ ]
Metal each metal species in LIST-I with their properties in LIST-II, and choose the correct option

• A. I $\to$ R, T; II $\to$ P, S; III $\to$ Q, T; IV $\to$ P , Q
• B. I $\to$ R, S; II $\to$ P , T; III $\to$ P, Q; IV $\to$ Q, T
• C. I $\to$ P, R; II $\to$ R, S; III $\to$ R, T; IV $\to$ P, T
• D. I $\to$ Q, T; II $\to$ S, T; III $\to$ P, T; IV $\to$ Q, R

Answer 1

Answer: (A)

(1) ${\left[Cr(CN{)}_6\right]}^{4-}$
$C{r}^{+2}=[Ar{]}_{18}3d^{4}4s^0;$ low spin complex

$P,R,T$
(2) ${\left[RuC{l}_6\right]}^{2-}$
$R{u}^{+4}=[Kr{]}_{36}4d^{4}5s^0$; low spin complex

$P,R,S,T$
(3) ${\left[Cr{\left(H_{2}O\right)}_6\right]}^{2+}$
$C{r}^{+2}=[Ar{]}_{18}3d^{4}4s^0$; high spin complex

$Q,T$
(4) ${\left[Fe{\left(H_{2}O\right)}_6\right]}^{2+}$
$F{e}^{+2}=[Ar{]}_{18}3d^6;$ High spin complex

$P,Q$