Question

The calculated spin only magnetic moment of $C{r}^{2+}$ is :

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• A. $5.92BM$
• B. $4.90BM$
• C. $2.84BM$
• D. $3.87BM$

Answer 1

The correct option is B $4.90BM$

Electronic configuration
$C{r}^{2+}:\left[Ar\right]3d^4$
No. of unpaired electron = 4
$\mu =\sqrt{n(n+2)}BM$
$\mu =\sqrt{4(4+2)}BM$
$\mu \approx 4.90BM$