Molarity Calculator
Calculate the molarity of a solution. Enter solute mass, solute formula weight (MW), and final volume of the solution.
Solution Formulation
Specify mass, formula weight, and volume.
Calculated Molarity
* Equal to 1000.0 mM (millimolar).
Expert Tip
Molarity is temperature-dependent because liquid volumes expand and contract with temperature. For high-precision physical chemistry work, molality (moles/kg solvent) is preferred.
Methodology & Equations
Molarity Formula
Molarity (M) represents the concentration of a solute in solution, calculated as moles of solute divided by liters of solvent:
Standard Solution Preparation
To prepare a solution of known molarity:
- 1. Weigh out the target mass of solute.
- 2. Dissolve solute in a volume of solvent slightly less than the target final volume.
- 3. Add solvent up to the final target volume mark using a volumetric flask.
How to Calculate Molarity of a Solution
Molarity (M) defines the concentration of a solute in a solvent as moles per liter:
Find Solute Moles
Divide the mass of solute (g) by its molecular weight (g/mol) to get the moles of solute: Moles = Mass / Molecular Weight.
Define Solution Volume in Liters
Convert milliliters or other units to Liters (L).
Divide Moles by Volume
Use the formula: Molarity (M) = Moles of Solute / Liters of Solution.
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