39. what particles are found in the nucleus of an atom?
what is the charge of the nucleus?

Nucleus of the atom has proton and neutron particles.

The charge of the nucleus  equals to the number of protons.

Explanation:

Nucleus of the atom has proton and neutron particles.

Proton has charge +1.

Neutron has charge 0.

So, the charge of the nucleus  equals to the number of protons.

For example,

if nucleus of carbon has 6 protons,  charge of this nucleus is +6.