Percent solutions
Make a percent solution or convert between percent, mg/mL, ppm and molarity.
Result
Formula
% w/v is grams per 100 mL, % v/v is mL per 100 mL, % w/w is grams per 100 g. Conversions pivot through g/L: % w/v × 10 = g/L, ppm ÷ 1000 × ρsolution = g/L, % w/w × 10 × ρsolution = g/L, % v/v × 10 × ρsolute = g/L, and g/L ÷ MW = mol/L. Dilute aqueous solutions may assume ρ = 1.00 g/mL.
Questions
What is the difference between % w/v, % v/v and % w/w?
% w/v is grams of solute per 100 mL of solution, used for solids. % v/v is millilitres of solute per 100 mL, used for liquids like ethanol. % w/w is grams per 100 g of solution and is how concentrated acids are sold.
How do I convert % w/v to molarity?
Multiply by 10 to get grams per litre, then divide by the molar mass. 0.9 % w/v sodium chloride is 9 g/L, and 9 ÷ 58.44 = 0.154 mol/L.
When do I need a density?
For % w/w and ppm, because they are defined by mass and you need the solution density to get to a volume. For dilute aqueous solutions a density of 1.00 g/mL is a safe assumption, and the calculator offers that shortcut.