Question
Among, $\mathrm{Sc}, \mathrm{Mn}, \mathrm{Co}$ and Cu, identify the element with highest enthalpy of atomisation. The spin only magnetic moment value of that element in its +2 oxidation state is __________ BM (in nearest integer).
✓
Answer
4
Highest Co
$Co ^{-2}=( Ar ) 3 d^7$
$\begin{array}{l} n =3 \\ \mu=\sqrt{15}=3.87\end{array}$
Nearest integer $=4$
| Sc | Mn | Co | Cu | |
| Enthalpy of Atomisation (kJ/mole) | 326 | 281 | 425 | 339 |
$Co ^{-2}=( Ar ) 3 d^7$
$\begin{array}{l} n =3 \\ \mu=\sqrt{15}=3.87\end{array}$
Nearest integer $=4$
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