Molarity Calculator – Calculate Solution Concentration

Molarity Calculator

Calculate molarity, moles, volume, mass, solution dilution, mixing, and gas solubility with step-by-step solutions and detailed explanations.

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Molarity Calculator

Select calculation mode and enter values to calculate molarity, moles, volume, mass, dilution, mixing, or gas solubility

Calculation Mode

Moles (n) *

Number of moles of solute

Volume (V) *

Volume of solution

Key Concepts

Amount of Substance (n)

The amount of substance, measured in moles (mol), represents the number of particles (atoms, molecules, ions) in a sample. One mole contains $6.022 \times 10^{23}$ particles (Avogadro's constant).

Molarity (c)

Molarity is defined as the number of moles of solute per liter of solution: $c = \frac{n}{V}$ . It's the most common concentration unit in chemistry laboratories.

Molar Volume

At standard temperature and pressure (STP: 273.15 K, 101.325 kPa), one mole of any ideal gas occupies $22.4 \text{ L}$ . This is useful for converting between gas volumes and moles.

Practical Applications

Laboratory preparation: Calculate exact amounts needed to prepare solutions of specific concentrations.
Chemical reactions: Use molarity to determine stoichiometric relationships in reactions.
Quality control: Verify solution concentrations in manufacturing and pharmaceutical industries.
Dilution protocols: Prepare working solutions from stock solutions efficiently.

Important Notes

Always ensure units are consistent (convert mL to L when necessary).
Molarity depends on temperature - volume changes with temperature.
For gas solubility, actual results may differ if the gas reacts with water (e.g., HCl, NH₃).
When mixing solutions, ensure they contain the same solute to avoid precipitation.

How to Use This Calculator

Select a calculation mode, enter the required values, and click "Calculate" to get step-by-step solutions with detailed explanations.

Molarity: Calculate concentration from moles and volume using

c = \frac{n}{V}

Moles: Find the number of moles from molarity and volume using

n = c \times V

Volume: Determine the volume needed using

V = \frac{n}{c}

Mass: Convert between moles and mass using

m = n \times M

Dilution: Calculate using

C_1 V_1 = C_2 V_2

Mixing: Find final concentration using

C = \frac{C_1 V_1 + C_2 V_2}{V_1 + V_2}

Gas Solubility: Calculate molarity when gas dissolves in water.