Question

Name the element which lies in group IA and 3rd period. What is the valency of it and why?

Answer 1

Na, valency 1.

Step-by-step explanation:

Na -sodium.

This element is in the 1A group, so it has 1 electron on the last (valent) level.

So, only 1 electron can participate in forming chemical bond, and therefore the valency of Na is 1.