The Grams to Moles Calculator converts a mass measured in grams into an amount of substance measured in moles. This conversion is common in chemistry because chemical equations are based on quantities of particles and substances, while laboratory measurements are often made by mass.
Grams to Moles Formula
The basic relationship is moles = mass Γ· molar mass. Mass is entered in grams and molar mass is normally expressed in grams per mole.
How to Use the Calculator
- Enter the mass of the substance in grams.
- Enter or select the correct molar mass.
- Calculate the amount in moles.
- Check that the molar mass corresponds to the actual substance and formula.
Example
Water has a molar mass of about 18.015 g/mol. For 36.03 g of water, the amount is 36.03 Γ· 18.015 = 2.00 mol.
Why Molar Mass Matters
Using the wrong chemical formula or molar mass can change the result significantly. For compounds, the molar mass is based on the atomic masses of all atoms represented in the chemical formula.