Mass Percent Calculator
Calculate mass percent of solute in a solution: mass% = (mass_solute / mass_solution) x 100.
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Enter the mass of the solute in grams and the total mass of the solution in grams. The calculator divides the solute mass by the total solution mass and multiplies by 100 to give mass percent.
About the Mass Percent Calculator
Mass percent (also called weight percent or w/w%) expresses concentration as the mass of solute per 100 grams of solution. It is widely used in industry, pharmacology, and everyday life. Unlike molarity, mass percent does not depend on temperature because it uses mass instead of volume.
Frequently Asked Questions
What is the difference between mass percent and mass of solute divided by mass of solvent?
Mass percent uses total solution mass (solute + solvent) as the denominator. Mass of solute divided by mass of solvent gives a different value, sometimes called the mass ratio. Always use total solution mass for mass percent.
How do I convert mass percent to molarity?
You need the solution density. Molarity = (mass% x density x 10) / molar_mass. For example, 10% NaCl with density 1.07 g/mL has molarity = (10 x 1.07 x 10) / 58.44 = 1.83 M.
What is a typical mass percent for saline solution?
Normal saline (0.9% NaCl) contains 0.9 g of NaCl per 100 g of solution. Household vinegar is about 5% acetic acid by mass. Concentrated sulfuric acid is about 96% by mass.