Question

An element x has mass number 35 and the number the of neutrons is 18 identy fy the group number and the period of x

Answer 1

solution-
we know,
atomic no.=atomic mass - no. of neutrons
=35-18
=17
it's electronic configuration = 2,8,7


so it's period is 3
& group is 17

Answer 2

Answer:

We know :

Atomic number = Mass number - No. of neutrons.

Atomic number = 35 - 18

= > 17

Electronic configuration :

2 , 8 , 7

Group no. = 17

Period no. = 3

Name of element is Chlorine (  Cl ) .