Question

An atom contains 3 protons n 4 electron find its atomic number n mass number

Answer 1

Atomic number = Number of protons = 3

Mass number = Number of protons + number of neutrons =3 + 4 = 7

Electronic configuration of the atom is 2,1(K,L)

Hence, its valency is 1.

Answer 2

Atomic no. = no. Of protons =3

Atomic mass =no. Of protons + electrons =7