General
✓✗When 0.15 g of a solute is dissolved in 15 g of a solvent, the boiling point is raised by 0.216 °C. If the molal elevation constant for the solvent is 2.16 K kg mol−1, the molar mass of the solute is
- 1.01 g mol−1
- 1000 g mol−1
- 10.1 g mol−1
- 100 g mol−1
General
✓✗A 0.0106 mol kg−1 aqueous solution of ethanoic acid has a van't Hoff factor of 1.041. The dissociation constant Ka is approximately (in units of 10−5)
- 168.10
- 43.46
- 0.18
- 1.86
General
✓✗Raoult's law becomes a special case of Henry's law when
- the solution is very concentrated
- the temperature is 0 K
- the solute is non-volatile
- KH becomes equal to the vapour pressure of the pure component
General
✓✗A sample of sea water contains 5.8 × 10−3 g of dissolved oxygen per kilogram. The concentration of oxygen in ppm is
- 58.0 ppm
- 0.6 ppm
- 5800.0 ppm
- 5.8 ppm
General
✓✗The relative lowering of vapour pressure of an aqueous solution of a non-volatile non-electrolyte is 0.018. The molality of the solution is (use the dilute-solution approximation)
- 1.00 m
- 0.50 m
- 18.00 m
- 0.02 m
General
✓✗An aqueous solution of glucose is 10% by mass. Its molality is (molar mass of glucose 180 g mol−1)
- 0.062 m
- 0.556 m
- 1.110 m
- 0.617 m
General
✓✗Which of the following 0.10 m aqueous solutions will have the lowest freezing point?
- Al2(SO4)3
- C5H10O5
- KI
- C12H22O11
General
✓✗When a non-volatile solute is added to a solvent, the vapour pressure of the solution
- remains unchanged
- increases
- becomes zero
- decreases
General
✓✗In a one molal solution that contains 0.5 mol of a solute, there is
- 500 g of solvent
- 500 mL of solvent
- 1000 g of solvent
- 100 mL of solvent
General
✓✗The boiling point of a solution of 0.1 mol of a solute in 500 g of water is 100.104 °C. If the solute is a non-electrolyte, Kb of water deduced is
- 2.08 K kg mol−1
- 0.02 K kg mol−1
- 1.04 K kg mol−1
- 0.52 K kg mol−1
General
✓✗Which of the following does NOT affect the solubility of a gas in a liquid?
- The partial pressure of the gas
- The temperature
- The nature of the gas
- The volume of the vessel at constant partial pressure
General
✓✗A 1.0 molal aqueous solution of a non-electrolyte is cooled to −3.72 °C. The fraction of water that separates as ice is (Kf = 1.86 K kg mol−1)
- 0.50
- 0.75
- 0.25
- 0.33
General
✓✗The mole fraction of a gas in water is 6 × 10−5 at a partial pressure of 1 bar. The Henry's law constant of the gas is
- 1.67 × 10−4 bar
- 6 × 10−5 bar
- 1.67 × 104 bar
- 6 × 105 bar
General
✓✗For a solute that dimerises completely in a solvent, the van't Hoff factor is
- 1
- 0.25
- 2
- 0.5
General
✓✗The SI-compatible unit of the Henry's law constant KH (for p = KHx) is the same as that of
- mole fraction
- concentration
- temperature
- pressure