๐Ÿงชap chemistry review

Atomic Number

Written by the Fiveable Content Team โ€ข Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examโ€ขWritten by the Fiveable Content Team โ€ข Last updated September 2025

Definition

The atomic number is equal to the number protons found in an atom's nucleus. It defines what element an atom is and its place on the periodic table.