How to Calculate Concentration If Concentration Units Are Not Specified
If concentration units are not specified, when given a percent It is usually always volume per volume for liquids and grams per mL for dissolved solids. (0.05 grams / 100 mL) * 20 mL = 0.010 grams of Bromophenol blue in 20 mL of water makes 0.05% (mass/volume) bromophenol blue. The dye is not very soluble. But your solution will be really blue. https://www.youtube.com/watch?v=pGeLjmxbe84
If concentration units are not specified, when given a percent It is usually always volume per volume for liquids and grams per mL for dissolved solids. (0.05 grams / 100 mL) * 20 mL = 0.010 grams of Bromophenol blue in 20 mL of water makes 0.05% (mass/volume) bromophenol blue. The dye is not very soluble. But your solution will be really blue. https://www.youtube.com/watch?v=pGeLjmxbe84