Question

an element mass no 35 and atomic no 17.find the no of neutons . the no.
of valance eletons

Answer 1

mass = no. of protons + no. of neutrons

and no. of p = no. of e =atomic number.

applying the above knowledge we get no of neutrons =35-17

=18.

no of valence electrons

electronic configuration =2,8,7

therefore valence electrons =7