Question

According to the label on the skim milk, 1 cup (244 mL) of skim milk contains 9.00 g pf protein. Assuming the density of the skim milk is 1.10 g/mL, what should the mass percent of protein in milk be?

Answer 1

244 mL of skim milk has a mass of 244mL*1.1g/mL = 268.4 g
If 9.0 g of that is protein, the protein mass fraction is 0.0335, or 3.35% protein.