Question

which one has the higher ionization energy li or f

Answer 1

li have the highest ionisation

Answer 2

Ionisation energy/enthalpy : Ionisation enthalpy is the energy required to remove the most loosely held electron from the outermost shell of the atom.

Electronic configuration of the elements:

Li: 1s²2s¹

F: 1s²2s²2p⁵

Here in case of Li the outermost electron is to be removed from 2s¹, and in F the outermost electron to be removed is from 2p⁵

# electrons in s orbital is ,more penetrated deeply near the nucleus, whereas the electrons of p orbitals are less penetrated. Hence removal of electron from p orbital is easier than s orbital.

Hence more energy is required for electrons to be pulled from s orbital of Li atom.

So,Li have higher ionization energy.