JEE Main20207 Jan 2020Morning ShiftChemistrySolutionsActual
At 35 o C , the vapour pressure of C S 2 , is 512 m m Hg and that of acetone is 144 m m H g . A solution of C S 2 in acetone has a total vapour pressure of 600 m m H g . The false statement amongst the following is:
Options
- ARaoult's law is not obeyed by this system
- Ba mixture of 100 m L C S 2 and 100 m L acetone has a volume < 200 m L
- CC S 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 100 m L C S 2 and 100 m L acetone has a volume < 200 m L
Step-by-step solution
P observed = 600 P Cal = P A 0 x A +P B 0 x B = 512 x + 344 − 344 x = 168 x + 344 = 512 (If x = 1 for maximum value) Thus, P cal < P observed Thus' the process is deviated from Raoult's law, showing positive deviation from Raoult's law. ΔH > 0   , i.e., is absorbed