Advertisements
Advertisements
Question
Which of the following 0.10 m aqueous solutions will have the lowest freezing point?
Options
Al2(SO4)3
C5H10O5
KI
C12H22O11
Advertisements
Solution
Al2(SO4)3
Explanation:
Freezing point depression depends on the number of particles in the Van’t Hoff factor (i). Al2(SO4)3 dissociates into 5 ions \[\ce{(2 Al^{3+} + 3 SO^2-_4)}\], producing the maximum number of particles, and hence causes the greatest depression in freezing point.
RELATED QUESTIONS
Define Cryoscopic constant.
Calculate the freezing point of a solution containing 60 g of glucose (Molar mass = 180 g mol–1) in 250 g of water. (Kf of water = 1.86 K kg mol–1)
Give reasons for the following:
Measurement of osmotic pressure method is preferred for the determination of molar masses of macromolecules such as proteins and polymers.
A 4% solution(w/w) of sucrose (M = 342 g mol−1) in water has a freezing point of 271.15 K. Calculate the freezing point of 5% glucose (M = 180 g mol−1) in water.
(Given: Freezing point of pure water = 273.15 K)
0.01 M solution of KCl and BaCl2 are prepared in water. The freezing point of KCl is found to be – 2°C. What is the freezing point of BaCl2 to be completely ionised?
A solution containing 1.8 g of a compound (empirical formula CH2O) in 40 g of water is observed to freeze at –0.465° C. The molecular formula of the compound is (Kf of water = 1.86 kg K mol–1):
Which of the following statement is false?
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be ______.
1.2 mL of acetic acid is dissolved in water to make 2.0 L of solution. The depression in freezing point observed for this strength of acid is 0.0198° C. The percentage of dissociation of the acid is ______. [Nearest integer]
[Given: Density of acetic acid is 1.02 g mL–1, Molar mass of acetic acid is 60 g/mol.]
Kf(H2O) = 1.85 K kg mol–1
Out of the following 1.0 M aqueous solution, which one will show the largest freezing point depression?
