Work out dilution (m1v1 = m2v2) instantly with clear inputs, formula shown and shareable results.
Diluting a solution adds solvent but no solute, so the number of moles is unchanged: M1V1 = M2V2. Rearranging gives the final volume the stock must be made up to, and subtracting the stock volume tells you how much solvent to add. A 2 M stock taken as 25 mL and finished at 0.5 M must reach 100 mL, meaning 75 mL of solvent.
Dilution equation
M1 x V1 = M2 x V2
Solvent to add
solvent = V2 - V1
Only that both volumes use the same unit. Enter millilitres and the answer is in millilitres; the ratio is what does the work.
Because glassware is graduated to a total volume. The solvent figure is given as well for cases where you are adding to a fixed aliquot.