Which one of the following statements is false?
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Raoult’s law states that the vapour pressure of a components over a solution is proportional to its mole fraction
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Two sucrose solutions of same molality prepared in different solvents will have the same freezing point depression
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The correct order of osmotic pressure for 0.01 M aqueous solution of each compound is BaCl2 > KCl > CH3COOH > sucrose
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The osmotic pressure (π) = MRT, where M is the molarity of the solution
B.
Two sucrose solutions of same molality prepared in different solvents will have the same freezing point depression
(a)pA = XA pAo : true
(b) ΔTf =Kfm
Kf is dependent on solvent
Thus is dependent on solvent
Thus freezing points [= t(solvent)- ΔTf) are different.
(c) i = [1 + (y-1) x]
y = number of ions
x = degree of ionisation
i = 3 for BaCl2 x = 1 (strong electrolyte)
i = 2 for KCl x = 1 (strong electrolyte)
i = (1+x) for CH3COOH x<i = (for BaCl2)>KCl>CH3COOH>Sucrose
(d) π = imRT = = MRT ; true (if van't Hoff factor i = 1
