When the number of protons and electrons possessed by an atom are unequal, the atom

Answer : When the number of protons and electrons possessed by an atom are unequal, the atom is charged.

Explanation :

Atomic number is defined as the number of protons or electrons that are present in a neutral atom.

Atomic number = number of protons = number of electrons

For the neutral atom, the number of protons and electrons are equal. But, they are unequal when the atoms present in the form of ions or the atom has some charge.

An ion is formed when an atom looses or gains electron.

When an atom looses electrons, it will form a positive ion known as cation.

When an atom gains electrons, it will form a negative ion known as anion.

For example : The neutral atom Na has equal number of protons and electrons i.e 11 but ion has unequal number of protons and electrons that means it has 11 number of protons and 10 number of electrons.

Hence, when the number of protons and electrons possessed by an atom are unequal, the atom is charged.