Size Duel deck / The body, cells and particles
Proton
Mass: rest mass
0 mg (0 oz)
The nucleus of an ordinary hydrogen atom is a single proton.
Sources and checks
Checked 2026-10-21: Researched by Codex (two independent publishers, verbatim quotes); every counted quote re-found on its page by the server check (content-verify); scope and plausibility reviewed by Claude (AI build agent). Quotes are short passages from each source.
“1.672 621 925 95 e-27”NIST, CODATA 2022: source, retrieved 2026-10-21; quote re-found by the server check
“1,67262”Store norske leksikon: source, retrieved 2026-10-21; quote re-found by the server check
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