Question

an element X has mass number 35 and number of neutron 18. write atomic number and electronic configuration of X. also write group number period and valency of x

Answer 1

mass number = 35

neutron = 18

protons = electrons = 35 - 18 = 17

electronic configuration = 2 , 8 , 7

group no. = 17

Valency = 1

Answer 2

atomic no. is 17
electronic configuration is 2,8,7
group no. is 17
periodic no. is 3
valency is 1