d
Magnetic moment \((\mu)=\sqrt{n(n+2)} \,B M\)

\(\quad 3.83=\sqrt{n(n+2)}\)

\(3.83 \times 3.83=n^{2}+2 n\)

\(14.6689=n^{2}+2 n\)

\(n=3\)

Hence, number of unpaired electrons in d-subshell of penultimate shell of chromium \((Cr= 24 )\) \(=3\)

So, the configuration of chromium ion is

\(C r^{3+}=1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{3}\)

ln \(\left[C r\left(H_{2} O\right)_{6}\right] C l_{2},\) oxidation state of \(C r\) is \(+3\)

Hence, in \(3 \mathrm{d} ^3\) the distribution of electrons \(3 d_{x y}^{1}, 3 d_{y z}^{1}, 3 d_{z x}^{1}, 3 d_{x^{2}-y^{2}}^{0}, 3 d_{z^{2}}^{0}\)