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Question
Using Raoult’s law explain how the total vapour pressure over the solution is related to mole fraction of components in the following solutions.
\[\ce{NaCl(s) and H2O(l)}\]
Solution
For a solution containing non-volatile solute i.e. \[\ce{NaCl(s) and H2O(l)}\], the Raoult's law is applicable only to vaporisable component (1) i.e. \[\ce{H2O(l)}\] and total vapur pressure is written as
`p = p_1 = x_1p_1^0`
where `p_1^0` represents the vapour pressure of pure \[\ce{H2O(l)}\]
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