Solution Mixing Calculator
Final concentration when two solutions are combined.
Work out Solution Mixing. Final concentration when two solutions are combined. Says where the model stops being reliable.
Use 0 for pure solvent — that makes this a dilution.
Concentration after mixing
0.875 M
400 mL total
(C₁V₁ + C₂V₂) ÷ (V₁ + V₂). Moles add, volumes add, and the result is always between the two starting concentrations — mixing cannot produce something more concentrated than the stronger solution. If it appears to, an input is wrong. Volumes are assumed additive, which is very nearly true for dilute aqueous solutions and noticeably false for concentrated ones. Mixing equal volumes of ethanol and water gives about 96% of the expected volume, because the molecules pack together more tightly than either does alone. For serious work, make up to a final volume in a volumetric flask rather than adding two measured volumes together.
How the Solution Mixing Calculator works
Enter the concentration and volume of each solution to get what you end up with. Set one concentration to zero and this becomes a dilution calculation. The result is always between the two starting concentrations — if it is not, an input is wrong.
Also known as: mixing two solutions calculator · combining solutions concentration · final concentration after mixing · c1v1 c2v2 calculator
Frequently asked questions
How do I calculate the concentration after mixing?
(C₁V₁ + C₂V₂) ÷ (V₁ + V₂). Moles add and volumes add, so the final concentration is the total moles over the total volume.
Can mixing produce something more concentrated than both solutions?
No, never. The result is a weighted average, so it always lies between the two inputs. An answer outside that range means an input has been entered wrongly.
Are volumes really additive?
Nearly, for dilute aqueous solutions. Not for concentrated ones — equal volumes of ethanol and water give about 96% of the expected total, because the molecules pack more tightly together than apart.
How is this different from a dilution calculation?
It is the general case. C₁V₁ = C₂V₂ assumes the second solution is pure solvent; this handles two solutions of any concentration, and reduces to the dilution formula when one of them is zero.
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