Mole

Definition

A counting unit for a specific quantity of particles, originally the number of atoms in exactly 12 grams of Carbon-12.

The mole bridges the microscopic world of atoms and the macroscopic world of grams, liters, and gallons. It lets you translate freely between mass, moles, and particles, where particles can be atoms, molecules, or ions. An element’s atomic mass in u equals its molar mass in grams per mole, so one mole of any element has Avogadro’s number of atoms regardless of its mass.

Related concepts

Molar mass · Atomic mass and atomic weight · Stoichiometry

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Part of The Blueprint of Water · 📏 measurement