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In the series Sc (Z = 21) to Zn (Z = 30)...

In the series Sc (Z = 21) to Zn (Z = 30), enthalpy of atomisation of zinc is the lowest, i.e., `126 kJ. Mol^(-1)`. Why ?

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In the above mentioned series Sc (Z = 21) to Zn (Z = 30), all the metal atoms have one or more unpaired electrons in their outermost shell. On the contry, zinc `(3d^(10)4s^(2))` has no unpaired electron in the outershell, leading to very poor interatomic interactions. Therefore, enthalpy of atomisation of zinc is the lowest.
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