Mole Calculator
The Molarity or molar concentration of a solution is the ratio of moles of solute per liter of solution (mol/L, or M). The simplest way to calculate molarity is to divide the number of moles of solute by the volume of the solution. To first find the number of moles of a solute with a known mass, divide the mass of the solute (in g) by its molecular weight. Using 2.0 grams of sodium chloride (NaCl) in .05 L of water as an example:
Molecular weight of NaCl = 58.44 g/mol
2.0 g58.44 g/mol = 0.0342 moles of NaCl
Using that result, the molarity can now be calculated:
0.0342 mol.05 L = 0.0684463 M
Use the calculator below to find the molarity of a solution using the molecular weight and mass of the solute, the volume of the solution, or its concentration.
| Mass of Substance (g) | Molecular Weight (g/mol) |
| Number of Moles (mol) | |