In biology percentage solutions are often preferred to molar ones. A 1% solution would have 1 g of solute dissolved in a final volume of 100 ml of solution. This would be labeled as a weight/volume [w/v] percentage solution. For w/w, both solvent and solute would need to be weighed in the required ratios. Volume would accordingly be measured using a measuring cylinder, volumetric flask, pipette or similar. Labels should show what the percentage relationships are (w/v, w/w or v/v).
The molarity of a percentage solution (w/v) can be calculated using the molar mass of the solute used. For example, sucrose (table sugar) has a molar mass of a 342.34 g/mol. A 1% sucrose solution (100ml, w/v), therefore, is 0.029 molar, or 29 mM.