Question

Why is the first ionisation enthalpy of carbon atom is greater than that of boron whereas the revers is true for the second ionisation enthalpy?

Answer 1

Carbon is near to achieve its symmetry but boron there is only one electron in p orbital so it is easier to remove electron

Answer 2

Beacuse in case of carbon all e are paired and in stable state on the other hand boron have one unpaired e in it shell and boron want to in stable state that is complete 2s orbit thats why boron easily give e as compared to carbon