Question

a)What is the ionization energy (in kJ/mol) for the one-electron species, He+1 ?

b)What is the ionization energy (in kJ/mol) for the one-electron species, P+14 ?

Answer 1

Both the given ions are single species electron containing ions. So by BOHR's formula we know :

E= -13.6z²/n² ev

Since we have to calculate ionization energy, assuming the electrons in ground state n=1

a) For He⁺¹, z=2 so E= -13.6*2² = 54.4 ev or 8.72 x 10^-18 J

This is for one ion. For one mole it will be multiplied by avogadro number N = 6.62 x 10²³

E = 5.77 x 10⁶ KJ/mol

b) For P⁺¹⁴, z=15 so E = -13.6*15² = 3060 ev or 4.9 x 10^-16 J

For one mole, E = 3.2 x 10⁸ KJ/mol