Question

compare alkali metals with alkaline earth metals with respect to
1)atomic radii
2)ionization enthalpy

Answer 1

1) atomic metals:

alkaline earth metals have smaller size than alkali metals

2) ionasation enthalpy:

the 1st ionasation enthalpy of alkaline earth metals is higher but the 2nd ionasation enthalpy is lower than the alkali metals. it is because of in alkaline earth metals the nuclear charge is increase