Q11 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.

The electronic configuration is: 2,8,8,2

(a) Since total energy shells are 4, so it will belong to period 4.


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


The valency will be 2.


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