The core of an atom contains protons and

The core of the atom contains a nucleus. That nucleus is made up of protons and neutrons.

Protons are made up two up quarks and a down quark. Up quarks have a charge of +2/3 and down quarks have a charge of -1/3.

+2/3 + 2/3 -1/3 = +4/3 - 1/3 = +3/3 = +1. This means that protons have a positive charge.

Neutrons are made up of two down quarks and an up quark.

-1/3 - 1/3 + 2/3 = -2/3 + 2/3 = 0. This means that neutrons have no charge, or a neutral charge.

The core of Atom contains protons and neutrons. In chemistry, Proton is subatomic particles that carry a positive charge (+) while neutrons carry a negative charge (-). Neutrons and Protons are both called as Nucleons in which may be bind together to form atomic nuclei.  The atomic mass unit of protons and neutrons is also called as nucleons. Atomic mass number or nucleon number is the number referred to the mass number of protons and neutrons found in the nucleus.