Q1 / 160 · AP EAMCET 2020 (17 Sep Shift 2) · Chemistry
Which of the following pairs of solutions is expected to be isotonic at same temperature?
- A\(0.1 \mathrm{M}\) urea and \(0.1 \mathrm{M} \mathrm{NaCl}\)
- B\(0.1 \mathrm{M}\) glucose and \(0.2 \mathrm{M} \mathrm{NaCl}\)
- C\(0.1 \mathrm{M} \mathrm{NaCl}\) and \(0.1 \mathrm{M} \mathrm{CH}_3 \mathrm{COOH}\)
- Correct answerD\(0.1 \mathrm{M} \mathrm{NaCl}\) and \(0.1 \mathrm{M} \mathrm{KNO}_3\)
Solution
Two solutions of same osmotic pressure \((\pi)\) are isotonic solutions.
\(\begin{aligned}
\pi_1(0.1 \mathrm{M} \mathrm{NaCl}) & =0.1 \times R T \times 2 \\
\pi_2\left(0.1 \mathrm{M} \mathrm{KNO}_3\right) & =0.1 \times R T \times 2
\end{aligned}\)
So, \(\pi,(0.1 \mathrm{M} \mathrm{NaCl})=\pi_2\left(0.1 \mathrm{M} \mathrm{KNO}_3\right)\) at same temperature.
Hence, the correct answer is option: 'D'.