Question

Atomic no. Of an element x is 15 and mass no. Is 31 what is the valency of atom of this elements

Answer 1

ATOMIC NO. ----> 15

MASS NO. -------> 31

ELECTRONIC CONFIGURATION ------> 2, 8, 5

VALENCY ------> - 3

Answer 2

x is phosphorus whose have the 3

$p {3}^{ - }$