The
proton is a subatomic particle of one unit positive
electric charge. The
nucleus of the
hydrogen atom, H
+, is a single proton. The nuclei of other atoms are composed of
neutrons and protons held together by the
strong nuclear force. The number of protons in the nucleus determines the chemical properties of the atom and what
chemical element it is.
A proton has a mass of 1.6726231 * 10-27 kg, which is about 1800 times heavier than an electron.
Protons are classified as baryons and are composed of two up quarks and one down quark, which are also held together by the strong nuclear force.
See also particle physics, chemistry, proton decay
Proton is also a Malaysian car factory.