S C Kheterpal, S N Dhawan and, P N Kapil Solutions for Chapter: Classification of Elements and Periodicity in Properties, Exercise 3: PROBLEMS FOR PRACTICE

Calculate the energy in joules required to convert all the atoms of sodium to sodium ions present in $2.3 \mathrm{mg}$ of sodium vapours. Ionisation enthalpy of sodium is $495 \mathrm{kJ} {\mathrm{mol}}^{-1}$(atomic mass of $\mathrm{Na}=23$).

The ionisation potential of hydrogen is $13.60 \mathrm{e} \mathrm{V}$, calculate the energy in $\mathrm{kJ}$ required to produce $0.1\mathrm{mol}$ of ${\mathrm{H}}^{+}$ ions. Given $1 \mathrm{eV}=96.49 \mathrm{kJ} {\mathrm{mol}}^{-1}$.

The first and second ionisation potentials of helium atoms are $24.58 \mathrm{eV}$ and $54.4 \mathrm{eV}$ respectively, calculate the energy in $\mathrm{kJ}$ required to produce one mole of ${\mathrm{He}}^{2+}$ ions.