% w/w
percent by weight
Concentrationexact by definition
Percent by weight is a mass fraction expressed in hundredths: 5% w/w means 5 grams of solute in 100 grams of solution. It is the unqualified meaning of "percent" in chemistry and the one this catalog's plain percent uses, so the factor is exactly 1.
Watch out: Note that it is per 100 g of SOLUTION, not of solvent. A 5% w/w solution is 5 g of solute in 95 g of water, not in 100 g. The difference is a twentieth at 5% and much worse at 50%.
| 1 % w/w | 1 % |
Solvers that use concentration