Here's why:
* Normal hydrogen: A typical hydrogen atom consists of one proton and one electron.
* Isotopes: Hydrogen has two isotopes: deuterium (one proton and one neutron) and tritium (one proton and two neutrons).
* Absence of a neutron: When a hydrogen atom lacks a neutron, it's only left with its proton. Since the electron is much lighter than the proton, the atom is essentially just a proton.
Therefore, a hydrogen atom without a neutron is essentially a proton, which is a positively charged ion.
