Chemistry

Moles Calculator

Convert grams to moles and molecules.

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Your numbers

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Moles
Moles
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Number of particles
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Millimoles
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Moles Calculator by TheCalcTools

How the Moles Calculator works

Enter the mass of the sample and the substance’s molar mass.

Moles are mass divided by molar mass.

Multiplying by Avogadro’s number gives the number of particles.

The formula

n = m ÷ MN = n × Nₐ

Worked example

Using the default values shown in the calculator:

Mass (g)18
Molar mass (g/mol)18.015
  1. 18 g of water ÷ 18.015 g/mol = 0.9992 mol.
  2. That is about 6.017 × 10^23 molecules.

Result:

Moles0.9992
Number of particles6.017 × 10^23
Millimoles999.17

Frequently asked questions

What is a mole?

The amount of substance that contains exactly 6.02214076 × 10²³ elementary entities, defined by fixing Avogadro’s constant.

How do I find the molar mass?

Add the atomic masses of every atom in the formula. Water, H₂O, is 2 × 1.008 + 15.999 = 18.015 g/mol.

Sources and further reading

Molarity CalculatorFind molarity and moles from a mass of solute dissolved in a volume Percent Yield CalculatorHow efficient was your reaction? Theoretical Yield CalculatorEnter the limiting reactant, the mole ratio and molar masses to get the maximum product… Limiting Reagent CalculatorEnter two reactants and the balanced equation coefficients to find which one runs out… Atom Economy Calculator (Green Chemistry)Enter the molar mass of the desired product and of all reactants to get the atom economy Titration CalculatorWork out an unknown concentration from a titration result

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