Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app

JEE Main 20207 JanuaryMorning Shift

Exam: JEE Main
Year: 2020
Date: 7 January
Shift: Morning Shift
Subject: Chemistry
Chapter: Solutions

JEE Main 2020 · 7 January · Morning Shift · Chemistry · Solutions

At 35 ^ o C, the vapour pressure of C S _ 2 , is 512mm Hg and that...

At

35{}^{o}C,

the vapour pressure of

C{S}_{2},

is

512mm

Hg and that of acetone is

144mmHg .

A solution of

C{S}_{2}

in acetone has a total vapour pressure of

600mmHg

. The false statement amongst the following is:

Options

ARaoult's law is not obeyed by this system
Ba mixture of $100mL{CS}_{2}$ and $100mL$ acetone has a volume $< 200mL$
C ${CS}_{2}$ and acetone are less attracted to each other than to themselves
Dheat must be absorbed in order to produce the solution at ${35}^{o}C$

Correct answer

B. a mixture of $100mL{CS}_{2}$ and $100mL$ acetone has a volume $< 200mL$

Step-by-step solution

{\text{P}}_{\text{observed}} = 600

{\text{P}}_{\text{Cal}} = {\text{P}}_{\text{A}}^{\text{0}} {\text{x}}_{\text{A}} {\text{+P}}_{\text{B}}^{\text{0}} {\text{x}}_{\text{B}}

= 512\text{x} + 344 - 344\text{x}

= 168\text{x} + 344

= 512

(If

\text{x} = 1

for maximum value)

Thus,

{\text{P}}_{\text{cal}} < {\text{P}}_{\text{observed}}

Thus' the process is deviated from Raoult's law, showing positive deviation from Raoult's law.

\Delta H > 0,

i.e., is absorbed

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 2026 Passage: Two volatile liquids A and B form an ideal solution. Consider a 5 molal solution… JEE Advanced 2026 Passage: Two volatile liquids A and B form an ideal solution. Consider a 5 molal solution… JEE Advanced 2026 Given below are two statements: Given: Molar mass of C, H, O, Cl are 12, 1, 16 and 35.5 g… JEE Main 2026 Which of the following statements are not correct? A. For water, magnitude of K_b is more… JEE Main 2026 Given below are two statements : Statement I : H _2 O molecules move from the chamber 1… JEE Main 2026 When 0.25 moles of a non-volatile, non-ionizable solute was dissolved in 1 mole of a… JEE Main 2026 20 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