How this calculator works
Choose a concentration definition and an unknown. Molarity counts moles per final solution volume. Mass-volume percent counts grams per 100 mL, while mass percent divides by complete solution mass. Density converts mass fraction into mass per volume, then molar mass converts grams into moles. Dilution conserves dissolved amount. All volume fields mean final solution volume; solvent-only volumes are not interchangeable with them.
Formula
c = n/V = m/(M V). % w/v = 100 m(g)/V(mL). Mass fraction = msolute/msolution. c = mass fraction x solution density / molar mass with consistent units. C1 V1 = C2 V2.
Worked example
Dissolving 0.5 mol to a final 2 L gives 0.25 mol/L. A 0.1 mol/L solution in 2 L contains 0.2 mol. Fifty grams in 2 L is 2.5% w/v.
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Frequently asked questions
Why are there several kinds of percentage?
Mass and volume denominators represent different quantities. State the basis whenever you report a percentage.
Which density should I enter?
The complete solution density at the relevant temperature and composition.
Can the dilution mode mix two concentrated stocks?
Use alligation for that case. The dilution balance assumes the added solvent contains none of the tracked solute.