The ionisation energy of hydrogen is

The ionisation energy of hydrogen is +13.6ev/atom1ev - 1.602 x 10-19J13.6ev - ??13.6 x 1.602 x 1019 J= 21.78 x 10-19J/atom1 atom energy - 21.78 x 10-19 J[1 mole] 6.023 x 1023 atoms energy - ?? J= 6.23 x 1023 x 21.78 x 10-19 J/mole= 131.224 x 104 J/mole[I.E]H = 1312 KJ/mole   [ 1J = 10-3 KJ]