Question

the atomic number of an element X is 17. Predict the following:- a) Its valency. b) Its valence electrons. c) Whether it is a metal or non - metal? d) Name of the element.

Answer 1

valency is 1
valence electrons are 7
non metal
chlorine

Answer 2

Explanation:

Atomic number of X = 17. Electronic configuration = 2, 8, 7

(a) Physical state → Gas (b) Chlorine (c) HCl (d) Non-metal (e) Cl2