Energy of an electron in the ground state of hydrogen atom is `-2.18 xx 10^(-18) J`. Calculate the inoisation enethalpy of atomic hydrogen in `J mol^(-1)`.

Explanation

Energy of an electron at infinity is taken as zero.
therefore The energy needed to remove an electron from ground state to infinity = energy at infinity - Energy at ground state = `0 - (-2.18 xx 10^(-18)J)= 2.18 xx 10^(-18)J`
Ionisation energy per mol of hydrogen = `2.18 xx 10^(-18) xx 6.02 xx 10^23/1000 = 1312.35 KJ mol^(-1)`