Question

although Boron is smaller in size as compared to berellium but the first ionization enthalpy of berellium is higher than Boron

Answer 1

According to periodic trends, boron should have a higher ionization energy but because its valence electron (2p1) is shielded by the 2s electrons, less energy is required to remove the the 2p electron(s) from a boron atom than is requried to remove the 2s electron from a beryllium atom.