CBSE Class 12-science Answered
the vapour pressure of a solvent decreased by 10mm in two columns of mercury when a non volatile solute was added to the solvent.the mole fraction of the solute in the solution is 0.2.what should be the mole fraction of the solvent if the decrease in the vapour pressure is to be 20mm of mercury
Asked by doctor srishty | 30 Jan, 2011, 08:05: PM
Expert Answer
The equation governing the change in the vapor pressure when you use a nonvolatile liquid or solid is just a special case of Raoult's Law, Ptot = PaXa + PbXb. Since the second component has a negligible vapor pressure (nonvolatile), Raoult's law reduces to
- P = P0X
where P is the vapor pressure of the mixture, P0 is the vapor pressure of the pure solvent and X is the mole fraction of the solvent.
Mole fraction of solute = 0.2
so mole fraction of solvent = 0.8
So
P-10 = 0.8(P)
So P= 10/0.2 = 50
In second case
50-20 = x.50
30/50= x
So mole fraction of solvent = 0.6
Answered by | 22 Feb, 2011, 12:46: PM
Concept Videos
CBSE 12-science - Chemistry
Asked by hannamaryphilip | 17 Apr, 2024, 11:20: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by sameerteli003 | 08 Apr, 2024, 11:48: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by rashmij34 | 27 Feb, 2024, 04:42: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by sagarmishra | 27 Feb, 2024, 04:01: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by kalandi.charan.407 | 08 Feb, 2024, 01:42: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by premkhare2006 | 24 Jan, 2024, 09:50: AM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by saritanohar22 | 13 Jan, 2024, 01:25: PM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by kaushikmisty07 | 31 Dec, 2023, 11:42: AM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by kamlesh.kumar.malee | 20 Dec, 2023, 06:59: AM
ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Asked by varinder2149 | 10 Dec, 2023, 08:21: PM
ANSWERED BY EXPERT