Question

An atom of an element contains 29 electrons and 35 neutrons. Deduce
(i) the number of protons

(ii) the electronic configuration of the element.

Answer 1

(i) For an atom to be neutral, the number of protons is equal to the number of electrons.
$\therefore$ Number of protons in the atom of the given element = 29

(ii) The electronic configuration of the atom is
$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}3d^{10}$