A) Raoulfs law states that the vapour pressure of a component over a solution is proportional to its mole fraction
B) The osmotic pressure\[(\pi )\]of a solution is given by the equation\[\pi =MRT,\]where M is the molarity of the solution
C) The correct order of osmotic pressure for 0.01 M aqueous solution of each compound is \[BaC{{l}_{2}}>KC1>C{{H}_{3}}COOH>sucrose\]
D) Two sucrose solutions of same molality prepared in different solvents will have the same freezing point depression
Correct Answer: D
Solution :
(a) \[{{p}_{A}}={{X}_{A}}P_{A}^{o}\] true (b)\[\pi =iMRT=MRT\]true (if vant Hoff factor\[i=1\]) (c) \[i=[1+(y-1)x]\] \[y=\]number of ions \[x=\]degree of ionisation \[i=3\]for\[BaC{{l}_{2}}x=1\] (strong electrolyte) \[i=2\]for \[KCl\text{ }x=1\] (strong electrolyte) \[i=(1+x)\]for\[C{{H}_{3}}COOH\text{ }x<<1\](weak) \[i=1\]for sucrose (non-electrolyte) \[i\] (for\[BaC{{l}_{2}}\])\[>KCl>C{{H}_{3}}COOH>sucrose\] Thus, is also true. (d)\[\Delta {{T}_{f}}={{K}_{f}}m.\] \[{{K}_{f}}\]is dependent on solvent. Thus, freezing points [\[=T\](solvent)\[-\Delta {{T}_{f}}\]) are different. Thus, (d) is false.
You need to login to perform this action.
You will be redirected in
3 sec
