Question

The first four ionisation energy values of element an element are191,578,872and5962kcal. The no of valence electron in the element is.
a.1
b.2
c.3
d.4

Answer 1

Given 4 ionization energies are in order

191 , 578, 872 , 5962

This shows that after removal of 3 electrons the increase in ionization energy is too high and this indicates that it is the most stable state.
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Note:-
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$\bf \: the \: \: most \: \: stable \: \: state \: \: is \: \: octet \: \: state \\ \\ i.e. \bf \: \: valence \: \: electron = 8$
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Thus, there are 3 more electrons in the element after its last octet to be filled.

So the valence electrons in the element is 3.

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$\bf Thus \: \: the \: \: required \: \: answer \: \: is \: \: option \: \: c \\ \\ \bf \: PROUD \: \: TO \: \: HELP \: \: YOU.$♥️

Answer 2

4 is the correct answer