One Hydrogen atom can contain a proton, and an electron; or it can contain a proton and an electron, and one or two neutrons, known as deuterium, and tritium, respectively. Protons are each made of three Quarks, as well as are neutrons. Quarks come with a 1/3 or 2/3 +, or - charge. read more
Therefore for two hydrogen atoms, the number of subatomic particles can be 8, (no neutrons), 11 ( one neutron), 14 (two neutrons), 17 (three neutrons), or 20 (four neutrons). There are also Gluons (energy particles) holding the quarks together; but gluons are above my pay grade, I know nothing about them. read more