Molarity Calculator
Calculate concentration, mass, molecular weight, or volume using the molarity equation
M = m / (MW × V)
Molarity (M)
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Mass (m)
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Molecular Weight (MW)
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Volume (V)
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Calculation Result
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Molarity (M) = Mass (g) / [Molecular Weight (g/mol) × Volume (L)]
Understanding Molarity
Molarity Formula
Molarity (M) is a measure of the concentration of a solute in a solution, expressed as the number of moles of solute per liter of solution:
M = m / (MW × V)
Where:
- M is the molarity (mol/L)
- m is the mass of the solute (g)
- MW is the molecular weight of the solute (g/mol)
- V is the volume of the solution (L)
This formula is fundamental in chemistry for preparing solutions and calculating concentrations.
Unit Conversion Factors
| Unit | Conversion to Base |
|---|---|
| 1 kilogram (kg) | 1000 grams |
| 1 milligram (mg) | 0.001 grams |
| 1 pound (lb) | 453.592 grams |
| 1 ounce (oz) | 28.3495 grams |
| 1 milliliter (mL) | 0.001 liters |
| 1 cubic meter (m³) | 1000 liters |
| 1 gallon (gal) | 3.78541 liters |
| 1 cubic inch (in³) | 0.0163871 liters |
All calculations convert to base units (grams and liters) before computation.
Example Calculation
To prepare 500 mL of 1 M NaCl solution (MW=58.44 g/mol):
- Convert volume to liters: 500 mL = 0.5 L
- Calculate mass: m = M × MW × V = 1 × 58.44 × 0.5 = 29.22 g
- Dissolve 29.22 g of NaCl in water and bring to 500 mL final volume
This calculator handles all unit conversions automatically, so you can input values in any supported unit.