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(b) a solution that shows negative deviation from Raoult's law.

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Dalton’s law

P total = p 1+ p2Where,

P total -Total pressure p1 ,p 2 -Partial pressure of component.

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Composition of liquid phase :

x1= p 1/ p 10

= partial pressure of component /vapour pressure of pure component

Composition in aseous phase !" 1= p 1/ P

= partial pressure of component /total pressure#aoult$s la% &ecomes

" iP=x iP isat 'i=1,2,()..n*Where!

"i = apor-phase mole fraction.xi = i ui -phase mole fraction.Pi = apor pressure of pure species i at the T of the s"stem."i P = Partial pressure of species i.

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VLE by Modified Raoult’s Law

"i P = xi i P isat ' i= 1,2,).., *

Wherei = ctivit" coefficient.

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T-x-y dia !am"boilin point dia !am

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Effe#t of $a!yin p!essu!e on equilib!iumdia !am

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%-x-y Dia !am

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u acit"! 3t is erive from atin, expresse asfleetness or escapin ten enc". 3t is useto stu " extensivel" phase an chemical reactione uili&rium.

G = RT ln f + ɵ

- Is an constant depends on temperature and natureɵof gas.

fu acit" has same units as pressure for an i eal as.

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ti$ity #oeffi#ient equations

Wohl$s three suffix e uation 4ar ules e uation an laar e uation Wilson e uation on ran om t%o li ui ' #T *e uation 5niversal uasi 6chemical '5 375 C*e uation 5niversal functional activit" coefficient '5 3 C*

metho