Question

can you Describe how protons, neutrons, and electrons each affect the charge and mass of an atom.

Answer 1

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Each proton raises the charge of the atom by +1. Each electron has an opposite charge of -1. In atoms the number of +1 and -1 charges will be equal, canceling each other out. Neutrons are neutral, so they don't have an effect.

Protons and neutrons both have a relative mass of just over one (compared to carbon-12 having a mass of exactly 12). Electrons have a relative mass of only 1/1840, which some people think is negligible.