. The electronic configuration of an element X is 2, 8, 8, 2. To which (a) period and

 (b) group of the modern periodic table does 'X' belong? State its valency. Justify your answer in each case

Best Answer

Ans. Element: 'X', Electronic configuration: 2, 8, 8, 2

(a) 'X' belongs to 4th period because 'X' has four energy shells and energy shell number corresponds to the period number.

(b) 'X' belong to 2nd group because 'X' has 2 electrons in its outermost shell and valence electrons (1, 2) corresponds to the group number of the element Valency:


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