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Science

What is The proton?

A proton is a positively charged particle found in the nucleus of every atom. The number of protons defines what element an atom is — for example, every hydrogen atom has one proton, and every carbon atom has six.

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Key things to understand

  • 1It's a positively charged particle in the atomic nucleus.
  • 2The number of protons defines the element.
  • 3It's far heavier than an electron.
  • 4Protons and neutrons make up the nucleus.

Frequently asked questions

What is a proton?
A positively charged particle in an atom's nucleus; the number of protons determines the element.
What's the difference between a proton and an electron?
Protons are positive and sit in the nucleus; electrons are negative and orbit around it.
Why does proton number matter?
It defines the element — change the proton count and you change which element the atom is.

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