Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main 201910 JanuaryEvening Shift
Exam
JEE Main
Year
2019
Date
10 January
Shift
Evening Shift
Subject
Chemistry
Chapter
Solutions

JEE Main 2019 · 10 January · Evening Shift · Chemistry · Solutions

The elevation in boiling point for 1 molal solution of glucose is...

The elevation in boiling point for 11 molal solution of glucose is 2K2K. The depression in freezing point for 22 molal solution of glucose in the same solvent is 2K.2K . The relation between Kb{K}_{b} and Kf{K}_{f} is:

Options

  1. AKb=2Kf{K}_{b} = 2{K}_{f}
  2. BKb=1.5Kf{K}_{b} = 1 .5 {K}_{f}
  3. CKb=Kf{K}_{b} = {K}_{f}
  4. DKb=0.5Kf{K}_{b} = 0 .5 {K}_{f}

Correct answer

A. Kb=2Kf{K}_{b} = 2{K}_{f}

Step-by-step solution

Freezing point depression refers to the lowering of the freezing point of solvent upon the addition of solute. Boiling point elevation refers to the increase in the boiling point of a solvent upon the addition of a solute.

∆Tb=iKbm⇒2=iKb×1............(i)<br/><br/>∆ {T}_{b} = {iK}_{b}m ⇒ 2 = {iK}_{b} \times 1 . . . . . . . . . . . . \left(i\right)<br /><br />∆ {T}_{f} = {iK}_{f}m ⇒ 2 = {iK}_{f} \times 2 . . . . . . . . . . . . . . . \left(ii\right)<br/><br/>Dividing(iii)<br /><br />Dividing \left(\dfrac{i}{ii}\right),

1=Kb2Kf1 = \dfrac{{K}_{b}}{2{K}_{f}}

Kb=2Kf{K}_{b} = 2{K}_{f}

Practice Solutions on Quantrex Academy →

More from Solutions

In a solvent S , a compound B is partially dissociated into C and D as given below: B… JEE Advanced 2026Passage: Two volatile liquids A and B form an ideal solution. Consider a 5 molal solution… JEE Advanced 2026Passage: Two volatile liquids A and B form an ideal solution. Consider a 5 molal solution… JEE Advanced 2026Given below are two statements: Given: Molar mass of C, H, O, Cl are 12, 1, 16 and 35.5 g… JEE Main 2026Which of the following statements are not correct? A. For water, magnitude of K_b is more… JEE Main 2026Given below are two statements : Statement I : H _2 O molecules move from the chamber 1… JEE Main 2026When 0.25 moles of a non-volatile, non-ionizable solute was dissolved in 1 mole of a… JEE Main 202620 g hemoglobin in a 1 L aqueous solution (A) at 300 K is separated from pure water by… JEE Main 2026 Full Solutions list All JEE Main PYQs