Question

An element belongs to 3 period and group 17 of the periodic table. What is its
valency?
​

Answer 1

Counting the periods and matching it with the periods of that of halogens, we find that period 3 has Chlorine. So, element is Chlorine. Chlorine has an atomic number equal to 17. ... An element with valency 3 could be Gallium (Ga).

Answer 2

Answer:

thank to dedo I have mark your answer as brainlist

id is in my following