Question

$x\%\left(w/v\right)$ aqueous solution of $HCHO$ and $y\%\left(w/v\right)$ aqueous solution of glucose are isotonic with each other. The ratio $x:y$ will be:

• A. $1:3$
• B. $1:6$
• C. $1:1$
• D. $1:4$

Answer 1

The correct option is B $1:6$

Two solutions having the same osmotic pressure across a semipermeable membrane is referred to as an isotonic solution.
Osmotic pressure, $\left(\pi \right)=CRT$
Where, $C$ is the concentration.
Let the osmotic pressure of $HCHO$ be ${\pi }_1$.
Osmotic pressure of glucose solution be ${\pi }_2$.
According to the question,
${\pi }_1={\pi }_2\therefore C_1=C_2\Rightarrow \frac{x/30}{0.1}=\frac{y/180}{0.1}\Rightarrow \frac{x}{y}=\frac{1}{6}$