Question

Arrange the following solutions in order of their increasing boiling points.
(i) \(10^{-4}\) M NaCl
(ii) \(10^{-4}\) M Urea
(iii) \(10^{-3}\) M NaCl
(iv) \(10^{-2}\) M NaCl

• A. \((ii) <(i) <(iii) <(iv)\)
• B. \((ii) <(i) \(\sim=\)\) (iii) \(<(iv)\)
• C. \((i) <(ii) <(iii) <(iv)\)
• D. \((iv) <(iii) <(i) <(ii)\)

Hint:

For colligative properties like boiling point elevation, the more the solute particles (ions), the higher the boiling point. Solutions with higher concentrations or higher ionization will have higher boiling points.

Answer 1

The Correct Option is A

\[ \Delta T_b = i \cdot K_b \cdot m \cdot \infty \cdot C \] Where \(C\) = concentration. \[ \text{Options} \quad \text{and their corresponding } i.C. \] \[ (i) \ 2 \times 10^{-4} \quad (ii) \ 1 \times 10^{-4} \quad (iii) \ 2 \times 10^{-3} \quad (iv) \ 2 \times 10^{-2} \] Boiling point order: 
\((ii) <(i) <(iii) <(iv)\)