Calculate the amount of water require to prepare 500g of 2.5% solution of sugar.

Mass percent = mass of solute / mass of solution .

Where mass of solution = mass of solute +  mass of solvent

Here mass of solution = 500g

Mass percent = 2.5 % 

Let the mass of solute be x.

Then 2.5 %  = x / 500

⇒ x = 12.5g

Hence mass of sugar is 12.5 g

∴ mass of solvent = mass of solution - mass of solute

∴ mass of solvent = 500 g - 12.5g

⇒ mass of solvent = 487.5 g 

Hence 487.5 g of water is required to prepare 500g of 2.5 % sugar solution.