Question

Compound that is both paramagnetic and coloured is

• A. $K_{2}C{r}_2{O}_7$
• B. $(N{H}_4{)}_2[TiC{l}_6]$
• C. $VOS{O}_4$
• D. $K_3[Cu(CN{)}_4]$

Answer 1

Answer: (C)

$K_{2}C{r}_2{O}_7$ contains $C{r}^{6+}(3d^0)$ which is diamagnetic but coloured due to charge transfer spectra. $(N{H}_4{)}_2[TiC{l}_6]$ contains $T{i}^{4+}(3d^0)$, which is diamagnetic and colourless.
$VOS{O}_4$ contains $V^{4+}(3d^1)$, which is paramagnetic and coloured.
$K_3[Cu(CN{)}_4]$ contains $C{u}^{+}(3d^{10})$, which is diamagnetic and colourless.