Answer:
the vapor pressure of water over the solution is 23.3445 mm Hg
Explanation:
From Raoult's law:
[tex]P_{solution} = x_{solvent} \times P^0_{solvent} [/tex]
where:
[tex]P_{solution}[/tex] is the observed pressure above the solution
[tex]x_{solvent}[/tex] is the molar fraction of solvent (here water)
[tex]P^0_{solvent}[/tex] is the vapor pressure of pure solvent at a given temperature
Moles of urea = (5 g)/(60.06 g/mol) = 0.083 mol
Moles of water = (100 g)/(18 g/mol) = 5.556 mol
Mole fraction of water = 5.556/(5.556 + 0.083) = 0.985
Therefore:
[tex]P_{solution} = 0.985 \times 23.7 \;mm\;Hg[/tex]
[tex]P_{solution} = 23.3445 \;mm\;Hg[/tex]
