Q9 of 58 Page 1

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.

Electronic configuration of ‘X’ is 2, 8, 8, 2.


(a) X belongs to period 4 because it has 4 energy shells.


(b) Since X has 2 valence electrons, so it belongs to group no. 2.


(c) The valency of X is 2 because it can acquire stable gas configuration by losing 2 electrons.


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