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Question
State Raoult’s law for a solution containing volatile components. Write two characteristics of the solution which obey Raoult’s law at all concentrations.
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Solution
Raoult's Law: According to Raoult's law, for a solution of two volatile liquids, the partial vapor pressure of each component of the solution is directly proportional to its mole fraction present in solution.
`"p"_1∝ "x"_1`
Implies that
`"P"_1="P"_1^circ "x"_1`
P1=Partial pressure of component 1.
x1 =mole fraction of component 1.
`"P"_1^circ`=pure vapour pressure of component 1.
Ideal solution obeys Raoult’s law at all concentrations.
The conditions obeyed are:
(i) ΔmixH=0
(ii) ΔmixV=0
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