L1 /
12
CH1012
BP. vs Vap.
COMPOSITION I
DGsoln = DHsoln - TDSsoln
Gsoln= Gibbs
Energy Hsoln= Enthalpy Ssoln= Entropy
1) DGsoln = +ve
immiscible liquids won’t mix
2) DGsoln = -ve miscible liquids
(i) DHsoln = 0
pA = poAxA, pB = poBxB
- ideal
solution behaviour
0 xA 1
T
a1
Boiling point curve
Vapour composition
curve
(here A is more volatile than B)
V.P. above mixture of
A
mole-fraction of A
V.P. pure liquid A
Temperature Composition
Diagram (p=1atm)
Vapour
Liquid
condense
heat liquid
Raoult’s Law
