Question

5 G of sugar is dissolved in 245ml of water calculate its concentration in terms of mass by volume percentage

Answer 1

it is given that, 5g of sugar is dissolved in 245ml of water.

here you didn't mention about density of sugar. because 245 ml is volume of water(i.e., solvent). for getting volume of solution, needs volume of solute.

and if 245 ml is volume of solution.

then,

weight of sugar = 5g

volume of solution = 245ml

now, mass by volume percentage = mass of solute/volume of solution × 100

= 5/245 × 100

= 1/49 × 100.

= 2.04% ≈ 2%

[ note : and if 245ml is volume of water.

then, we have require density of sugar.

let density of sugar is d.

then, volume of sugar = 5/d

now, volume of solution = 245 + 5/d

so, mass by volume percentage = 5/(245 + 5/d) × 100 , here I added both possibilities. now your choice, which one is given in your reference.. ]