Question

Which of the following has same number of electrons protons and neutrons. (a) Lithium (b) Phosphorus (c) Aluminium (d) Silicon

Answer 1

Atomic Mass of Li = 7 amu; P = 31 amu; Al = 27 amu; Si = 28 amu

Atomic Number Of Li = 3; P = 15; Al = 13; Si = 14

Lithium,

Protons = 3; Electrons = 3; Neutrons = 4

Phosphorus,

Protons = 15; Electrons = 15; Neutrons = 16

Aluminium,

Protons = 13; Electrons = 13; Neutrons = 14

Silicon,

Protons = 14; Electrons = 14; Neutrons = 14

Silicon is the element with same number of  electrons, protons and neutrons.

I hope this helps.