Science
What is a proton?
A proton is a positively charged particle found in the nucleus of every atom. The number of protons defines which element an atom is — one proton makes hydrogen, six make carbon — making protons the fundamental identity of matter.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains a proton.
Key things to understand
- 1It's a positively charged particle in the atom's nucleus.
- 2The number of protons determines the element.
- 3It's far heavier than an electron.
- 4It's made of even smaller particles called quarks.
- 5Protons and neutrons together form the nucleus.
Frequently asked questions
- What does a proton do in an atom?
- Its positive charge holds the negative electrons in orbit, and the number of protons defines which element the atom is.
- What is a proton made of?
- Three smaller particles called quarks, bound together by the strong nuclear force.
- How is a proton different from a neutron?
- Both sit in the nucleus and have similar mass, but the proton carries a positive charge while the neutron has none.