Solubility - Factors Affecting - UNSOLVED PRACTICE SET
Chapter: Solutions | Topic: Solubility Factors Affecting
SOLUBILITY - FACTORS AFFECTING - UNSOLVED PRACTICE SET
Topic: Solubility Factors Affecting
Multiple Choice Questions
Q1. The maximum amount of a solute that can be dissolved in a given amount of solvent at a specific temperature is called:
- Concentration
- Solubility
- Molarity
- Dilution
Q2. For most solid solutes, solubility in water:
- Decreases with increase in temperature
- Increases with increase in temperature
- Remains constant with temperature
- First increases then decreases
Q3. The solubility of gases in liquids:
- Increases with increase in temperature and pressure
- Decreases with increase in temperature but increases with increase in pressure
- Increases with increase in temperature but decreases with increase in pressure
- Remains unaffected by temperature and pressure
Q4. Which of the following factors does NOT affect the solubility of a solid in a liquid?
- Temperature
- Pressure
- Nature of solute and solvent
- Particle size of solute
Q5. According to the principle "like dissolves like," which of the following is most likely to dissolve in water?
- Benzene
- Iodine
- Ethanol
- Carbon tetrachloride
Q6. The solubility of CaO in water is an example of:
- Endothermic dissolution
- Exothermic dissolution
- Athermal dissolution
- None of the above
Short Answer Questions
Q7. State and explain the factors that affect the solubility of:
(a) A solid in a liquid
(b) A gas in a liquid
Q8. Why does the solubility of most solids increase with temperature, while the solubility of gases decreases with temperature?
Q9. Explain why common salt (NaCl) and sugar (sucrose) are both soluble in water despite having different chemical natures.
Q10. What is the effect of pressure on the solubility of:
(a) CO₂ in water
(b) NaCl in water
Explain your answer in each case.
Q11. Your mother adds sugar to hot milk for making kheer, and it dissolves quickly. But when she tries to add the same amount to cold milk, some sugar remains undissolved. Explain this observation.
Q12. Why does the solubility of gases in liquids increase with pressure? Explain with reference to Henry's law.
Long Answer Questions
Q13. Discuss the factors affecting the solubility of solids in liquids:
(a) Nature of solute and solvent — "like dissolves like" principle
(b) Effect of temperature on solubility — endothermic vs. exothermic dissolution
(c) Effect of pressure — negligible for solids
(d) Common ion effect on solubility
(e) Solubility curves and their interpretation
Illustrate with examples and solubility curves of NaCl, KNO₃, and Ca(OH)₂.
Q14. Explain the factors affecting the solubility of gases in liquids:
(a) Nature of gas and liquid — polar vs. non-polar interactions
(b) Effect of pressure — Henry's law
(c) Effect of temperature — why gas solubility decreases with temperature
(d) Effect of salting out
(e) Applications: carbonated beverages, aquatic life, decompression sickness ("the bends")
Q15. Solubility principles have direct relevance to Indian daily life and health. Discuss:
(a) Why kidney stones (calcium oxalate) form and how increased water intake prevents them
(b) How the solubility of oxygen in water affects fish populations in Indian rivers during summer
(c) Why tea leaves release more flavour in hot water than cold water
(d) The role of solubility in Ayurvedic medicine preparation (kwath, arishta, asava)
Numerical / Application-Based Problems
Q16. The solubility of KNO₃ at different temperatures is:
20°C: 31.6 g/100 g water
40°C: 63.9 g/100 g water
60°C: 110 g/100 g water
80°C: 169 g/100 g water
(a) Plot a solubility curve (solubility vs. temperature).
(b) Calculate the mass of KNO₃ that will crystallise when a saturated solution prepared at 80°C is cooled to 20°C, starting with 200 g water.
(c) Determine whether KNO₃ dissolution is endothermic or exothermic based on the data.
Q17. The solubility of oxygen in water at 1 atm is 0.043 g/L at 25°C and 0.056 g/L at 10°C.
(a) Calculate the percentage decrease in oxygen solubility when temperature rises from 10°C to 25°C.
(b) A fish tank contains 100 L of water at 30°C. If the oxygen solubility at 30°C is 0.038 g/L, calculate the total mass of dissolved oxygen. If fish consume 0.5 g O₂ per hour, how long before oxygen is depleted (assuming no replenishment)?
(c) Explain why fish die in large numbers in Indian lakes during summer heat waves.
Q18. A soft drink is bottled at 25°C under 4 atm pressure of CO₂. Henry's law constant for CO₂ in water at 25°C is 3.3 × 10⁻² mol/L·atm.
(a) Calculate the concentration of CO₂ in the soft drink.
(b) Calculate the volume of CO₂ released (at STP) when a 500 mL bottle is opened (pressure drops to 1 atm).
(c) Explain why soft drinks go "flat" when left open and why they are stored in refrigerators.
[Given: Molar volume at STP = 22.4 L/mol]