Question

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 ?

Answer 1

In the series , Sc to Zn , all elements have one or more unpaired electrons except zinc which has no unpaired electron as its outer electronic configuration is `3d^(10)4s^(2)`. Hence, atomic intermetallic bonding ( metal - metal bonding) is weakest in zinc. Therefore, enthalpy of atomisation is lowest.