4.1.5 Positive Ions

However, atoms can lose or gain electrons due to various interactions, forming charged particles known as ions:

• If an atom loses one or more electrons, it becomes a positively charged ion.
• If an atom gains one or more electrons, it becomes a negatively charged ion.

The atom is neutral as it has two positive protons and two negative electrons.

A helium atom that has lost or gained an electron is an ion.

If the ion has two positive protons but one negative electron, it is a positive ion.

If the ion has two positive protons but three negative electrons, it is a negative ion.