Question

An element x has mass no 35 and nu3tron 18 find the group

Answer 1

hey mate here is your answer

no. of protons=atomic no.=mass no.-no. of neutrons

atomic no.=35-18

=17

and as this element is having valency (-1)

it belongs to halogen family group no. 17

and as it has 3 shells it belongs to third period

so the element is chlorine

hope it will help you

mark me brainliest ✌✌✌

Answer 2

Mass number of a element = No of Protons/Atomic Number + No of Neutrons

No of Protons/Atomic Number = Mass number - No of neutrons

Atomic Number = 35 - 18 = 17

Electronic Configuration of Element X ⇒ 2,8,7

Valence Electron ⇒ 7

So Group number is ( 10 + 7 ) = 17