What is the difference between w/w, w/v, and v/v percentage?
w/w % is grams of solute per 100 grams of solution, w/v % is grams of solute per 100 mL of solution, and v/v % is milliliters of solute per 100 mL of solution. Each requires different formulas for molarity conversion. See also our use the Molar Volume Calculator.
When do I need to enter density for the calculation?
For w/v percentages, density is not needed. For w/w percentages, you need the solution density. For v/v percentages, you need the solute density to convert volume to mass.
How is molarity calculated from percentage concentration?
The formula depends on the percentage type: w/v uses M = (% × 10) / Molar Mass, w/w uses M = (% × density × 10) / Molar Mass, and v/v uses M = (% × solute density × 10) / Molar Mass. The factor 10 converts per 100 mL to per liter.
What units should I use for molar mass and density?
Enter molar mass in g/mol and density in g/mL. The calculator will automatically handle the unit conversions to give molarity in mol/L (M).
Why is the factor 10 used in the calculation?
The factor 10 converts the concentration from 'per 100 mL' (percentage basis) to 'per liter' (molarity basis), since 1 liter = 1000 mL and 1000/100 = 10.
Can I calculate molarity for very dilute or concentrated solutions?
Yes, the calculator works for any concentration from 0.001% to 100%. However, very high concentrations may require accurate density values for precise results.