🧪 Chemistry

Mole

Definition

The SI unit for the amount of a substance, equal to 6.022 × 10²³ particles (atoms, molecules, or ions) — known as Avogadro's number.

Why is Mole Important?

Mole is an essential chemistry concept used in laboratories, pharmaceutical development, environmental science, and industrial processes. Understanding this concept is critical for accurate chemical calculations, safe laboratory practices, and optimizing reactions.

Our chemistry calculators provide instant, accurate results for complex conversions and calculations, making lab work more efficient and reducing the risk of errors in critical measurements.

What is a Mole?

The mole (mol) is the SI unit for the amount of a substance, defined as exactly 6.02214076 × 10²³ particles (atoms, molecules, ions, or other entities). This number is known as Avogadro's number. The mole bridges the gap between the atomic scale and the human scale — allowing chemists to count atoms by weighing them.

Why Moles Matter

Without MolesWith Moles
"Mix 1.204×10²⁴ molecules of H₂ with 6.022×10²³ molecules of O₂""Mix 2 mol H₂ with 1 mol O₂"
Individual atoms are ~10⁻²⁶ kg1 mol of atoms weighs the molar mass in grams

Molar Mass Reference

SubstanceMolar Mass (g/mol)Meaning
Hydrogen (H₂)2.0161 mol H₂ weighs 2.016 g
Carbon (C)12.0111 mol C weighs 12.011 g
Water (H₂O)18.0151 mol H₂O = 18 mL ≈ 1 tbsp
Sodium chloride (NaCl)58.441 mol NaCl ≈ 2 tbsp table salt
Glucose (C₆H₁₂O₆)180.161 mol glucose ≈ ¾ cup sugar

Related Terms

Molar MassMolarityMolalitypHStoichiometryDilution

Mole — Frequently Asked Questions

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