Question

Question #b8ac0

Answer 1

Here the total number of ionization energy values of element X is `color(red)(4)`

So the total number of electrons in X atom should be 4 and the electronic configuration will be `1s^2 2s^2`

Hence the number of valance electron in the atom is `color(red)(2)`

The question is not clear enough and data given here is not realistic.e.g IE1>>>than IE2 etc.

I assumed that only 4 ionisation energy values of the atom are possible.

Another view of the same question given in the site.

http://www.meritnation.com/junior/ask-answer/question/the-successive-ionization-energies-for-element-x-is-given-as/classification-of-elements-and-periodicity-in-properties/9629511