Question

Does a hydrogen atom have neutrons?

Answer 1

The deuterium and trittium isotopes certainly do.

Explanation:

Most hydrogen nuclei have only the 1 nuclear particle: the protium isotope, `""^1H` is certainly abundant, and has no neutrons. However, some hydrogen nuclei contain one or two neutrons to give the `""^2H" deuterium"`, and `""^3H" tritium"` isotopes respectively.