🔋college physics i – introduction review

key term - Protons

Definition

Protons are positively charged subatomic particles found in the nucleus of an atom. They contribute to the atomic number and, therefore, the identity of an element.

5 Must Know Facts For Your Next Test

  1. Protons have a positive electric charge of +1e or approximately $1.602 \times 10^{-19}$ coulombs.
  2. The number of protons in an atom's nucleus is called its atomic number and defines the element.
  3. Protons are composed of three quarks: two up quarks and one down quark.
  4. Protons have a rest mass of approximately $1.6726 \times 10^{-27}$ kilograms, making them slightly less massive than neutrons but much more massive than electrons.
  5. In a neutral atom, the number of protons equals the number of electrons.

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