ExamBro
ExamBro
COMEDK · Chemistry · 17. Solutions

Which of the following is correct order of their increasing boiling points?

  1. A \(10^{-4} \mathrm{M} \mathrm{NaCl}>10^{-3} \mathrm{M} \mathrm{MgCl}_{2}>10^{-2} \mathrm{M} \mathrm{NaCl}\) \(>10^{-4} \mathrm{M}\) urea.
  2. B \(10^{-2} \mathrm{M} \mathrm{NaCl}>10^{-3} \mathrm{M} \mathrm{MgCl}_{2}>10^{-4} \mathrm{M} \mathrm{NaCl}\) \(>10^{-4} \mathrm{M}\) urea.
  3. C \(10^{-4} \mathrm{M}\) urea \(>10^{-4} \mathrm{M} \mathrm{NaCl}>10^{-3} \mathrm{M} \mathrm{MgCl}_{2}\) \(>10^{-2} \mathrm{M} \mathrm{NaCl}\).
  4. D \(10^{-2} \mathrm{M} \mathrm{NaCl}>10^{-3} \mathrm{M} \mathrm{MgCl}_{2}>10^{-4} \mathrm{M} \mathrm{NaCl}\) \(>10^{-4} \mathrm{M}\) urea.
Verified Solution

Answer & Solution

Correct Answer

(B) \(10^{-2} \mathrm{M} \mathrm{NaCl}>10^{-3} \mathrm{M} \mathrm{MgCl}_{2}>10^{-4} \mathrm{M} \mathrm{NaCl}\) \(>10^{-4} \mathrm{M}\) urea.

Step-by-step Solution

Detailed explanation

The elevation in boiling point is given by \(\Delta T_b = i \times K_b \times m\), where \(i\) is the van't Hoff factor and \(m\) is the molality. Since \(K_b\) is constant for the solvent, the boiling point is directly proportional to the product \(i \times m\). Calculate the…