Chemistry

Molarity Calculator

Find molarity and moles from a mass of solute dissolved in a volume.

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Your numbers

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Moles of solute
Moles of solute
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Millimoles
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Molarity (mol/L)
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Concentration (g/L)
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Molarity Calculator by TheCalcTools

How the Molarity Calculator works

Enter the mass of solute, its molar mass (sum of atomic masses) and the final volume of solution.

Moles are mass divided by molar mass.

Molarity is moles divided by litres of solution.

The formula

n = m ÷ Mc = n ÷ V

Worked example

Using the default values shown in the calculator:

Mass of solute (g)5.844
Molar mass (g/mol)58.44
Solution volume (mL)500
  1. Moles = 5.844 ÷ 58.44 = 0.1000 mol.
  2. Volume = 0.5 L, so molarity = 0.2000 mol/L.

Result:

Moles of solute0.1000
Millimoles100.00
Molarity (mol/L)0.2000
Concentration (g/L)11.688

Frequently asked questions

Is the volume that of the solvent or the solution?

Of the final solution. Dissolving a solute changes the volume slightly, so make up to the mark in a volumetric flask.

What is the molar mass of sodium chloride?

About 58.44 g/mol (Na 22.99 + Cl 35.45), which the defaults use.

Sources and further reading

Dilution Calculator (C1V1 = C2V2)How much stock solution do you need to make a diluted solution? Moles CalculatorConvert grams to moles and molecules pH CalculatorEnter a pH or concentration and get the other acid-base values Molality CalculatorEnter solute mass, molar mass and solvent mass to get the molality Mole Fraction CalculatorEnter the moles of each component to get mole fractions Normality CalculatorConvert molarity to normality, or find normality from mass and volume

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This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.