Page "Atom" Paragraph 30

The electron is by far the least massive of these particles at, with a negative electrical charge and a size that is too small to be measured using available techniques.

Protons have a positive charge and a mass 1, 836 times that of the electron, at, although this can be reduced by changes to the energy binding the proton into an atom.

Neutrons have no electrical charge and have a free mass of 1, 839 times the mass of electrons, or.

Neutrons and protons have comparable dimensions — on the order of — although the ' surface ' of these particles is not sharply defined.