First and second ionisation energies of `Be_((g)) are 900 kJ mol_(1) and 1750 kJ mol_(1)` approximately.
Claculate approximate percentage of `Be^(2+)_((g))` ions, if
1 g of `Be_((g))` absorbs 150 kJ of energy [atomic weight of Be is 9].

Explanation

(i) amount of energy absorbed by 1 g of Be to form
`Be^(+) and Be^(+2)`
(ii) energy required for conversion of 1 g `Be_((g)) into `Be^(+)` ions
(iii) calculation of additional amount of energy
(iv) conversion of `Be^(+)` ions to `Be^(+2)` ions
(v) 25%.