How do you calculate molar mass?

Add the molar mass of each atom in the chemical formula. For H₂O: 2 × 1.01 + 16.00 = 18.02 g/mol.

What is the difference between molar mass and molecular mass?

They are numerically equal; molar mass is expressed in g/mol (per mole), molecular mass in atomic mass units (per molecule).

Grade 11 · Chemistry

The mole and molar mass

Why it matters

Defining the mole and finding the molar mass of a compound.

Core20m readingPrerequisite: Atomic masses and Avogadro's hypothesis

What is molar mass in chemistry?

Short answer

Molar mass is the mass of one mole of a substance, in grams per mole (g/mol). For an element it equals the atomic mass on the periodic table; for a compound you add the molar masses of every atom in the formula. Molar mass is the bridge that converts between the mass of a sample and the number of moles it contains.

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Frequently asked questions

How do you calculate molar mass?: Add the molar mass of each atom in the chemical formula. For H₂O: 2 × 1.01 + 16.00 = 18.02 g/mol.
What is the difference between molar mass and molecular mass?: They are numerically equal; molar mass is expressed in g/mol (per mole), molecular mass in atomic mass units (per molecule).

What is molar mass in chemistry?

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Frequently asked questions