Q5 of 56 Page 1

How does the valency of elements very (i) in going down a group, and (ii) in going from left to right in a period of the periodic table?

(i) The valency of an element doesn’t change while going down the group.

Explanation: It remains the same as the number of valence electrons remains same in the elements along a group.


(ii) When going from left to right in a period of the periodic table, the valency increases from 1 to 4 and then it decreases from 4 to 0.


Explanation: This is because in a period, the number of valence electrons change along the period.


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