Question

A sugar solution with concentration 8.5% (w/w) is made by dissolving ‘X’ g of sugar in 450 g of water. The amount ‘X’ is

• A. 49.2 g
• B. 45.3 g
• C. 41.80 g
• D. 35 g

Answer 1

The correct option is C 41.80 g

Mass of solute = X g
Mass of solution = Mass of solute + Mass of solvent
= (X + 450) g
Concentration (w/w%) of solution $=\frac{\text{Mass of solute}}{\text{Mass of solution}}\times 100$
$\Rightarrow 8.5=\frac{X}{X+450}\times 100$
⇒ 100X = 8.5(X + 450)
⇒ 100X = 8.5X + 3825
⇒ 91.5X = 3825
$\Rightarrow X=\frac{3825}{91.5}$
⇒ X = 41.80 g
Hence, the correct answer is option (c).