# 8.2     In the series $Sc (z=21)$ to $Zn (z=30),$ the enthalpy of atomisation of zinc is the lowest, i.e.,   $126 \; kJ \; mol^{-1}$. Why?

The enthalpy of atomisation of zinc is lowest due to the absence of unpaired electron,which ie responsible formetallic bonding in the elements.Therefore, the inter-atomic bonding is weak in zinc($Zn$). Hence it has low enthalpy of atomisation.
The enthalpy of atomisation of zinc is lowest due to the absence of an unpaired electron, which is responsible for metallic bonding in the elements. Therefore, the inter-atomic bonding is weak in zinc($Zn$). Hence it has a low enthalpy of atomisation.