Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). It equals the atomic or molecular weight in unified atomic mass units.

How many grams in a mole of water?

Water (H₂O) has a molar mass of 18.015 g/mol. One mole of water = 18.015 grams.

How do I convert moles to grams?

Grams = Moles × Molar mass. For example, 2 mol of NaCl × 58.44 g/mol = 116.88 g.

How do I convert grams to moles?

Moles = Grams ÷ Molar mass. For example, 100 g of NaCl ÷ 58.44 g/mol = 1.711 mol.

What is Avogadro's number?

Avogadro's number is 6.022 × 10²³ particles per mole. Multiply moles by this number to get individual molecules or atoms.

Molar Mass Calculator

Find the molar mass of common elements and chemical compounds in g/mol. Instantly convert between moles, grams, and molecules.

Compound / Element

Input Type

Amount

Molar Mass

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Moles —

Grams —

Molecules (×10²³) —

How to Use This Calculator

Select a compound or element from the list.
Enter the amount in grams or moles.
Results show moles, grams, and number of molecules.

Formula

Grams = Moles × Molar mass

Moles = Grams ÷ Molar mass

Molecules = Moles × 6.022 × 10²³

Example

Example: 36.03 g of water (M = 18.015 g/mol) → 2.000 mol → 1.204 × 10²⁴ molecules.

Frequently Asked Questions

Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). It equals the atomic or molecular weight in unified atomic mass units.
Water (H₂O) has a molar mass of 18.015 g/mol. One mole of water = 18.015 grams.
Grams = Moles × Molar mass. For example, 2 mol of NaCl × 58.44 g/mol = 116.88 g.
Moles = Grams ÷ Molar mass. For example, 100 g of NaCl ÷ 58.44 g/mol = 1.711 mol.
Avogadro's number is 6.022 × 10²³ particles per mole. Multiply moles by this number to get individual molecules or atoms.

Molar Mass Calculator

How to Use This Calculator

Formula

Example

Frequently Asked Questions

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