Answer:
The atomic number represents the number of protons of that element.
Protons have a positive charge.
Protons are only one part of the nucleus of an atom
Another part of the nucleus are the neutrons.
Neutrons DO NOT have a charge. If they had a negative charge the nucleus could not exist, because the positive and negative charge would cause them to repel each other.
Electrons, those subatomic particles circling the nucleus have a negative charge.
When the number of electrons is equal to the number of protons, each positive and negative charge is balanced, has an equal and opposite charge, we the atom is neutral.
When an atom loses an electron, like when another atom has a stronger attraction for electrons, the atom which loses the electron now has more protons than electrons, so it now has a positive charge. That atom now has a name called an 'ion'. For each electron lost, the ion is designated as either +1(when loses one electron), 2+(when an atom loses 2 electrons), 3+(loses 3 electrons) and so on. Since the atom has more protons and less electrons, it is called a 'positive ion'
When an atom gains an electron, because it has a stronger force/affinity for electrons, it now has more electrons that protons. This is also called an ion. If an atom gains one electron, it is labelled -1(gains 1 electron), -2(gains 2 electrons), and so. This ion is called a negative ion.
So, an atom with equal number of protons and electrons is called a neutral atom