The statement “20 percent glucose in water by mass” signifies.

“20 percent glucose in water by mass” signifies that 20 gram of glucose dissolved in 100 gram of solution.

and  Mass of solution = Mass of solute + Mass of solvent

        Mass of solution= 20+  Mass of solvent=100

        Mass of solvent= 100-20= 80 g

Here, solvent is water.

So, we can say 20 % of glucose in water by mass means 20 gram of glucose is dissolved in 80 g of water.