Questions About Colligative Properties

June 04, 2025 Solutions

Questions About Colligative Properties

Multiple-Choice Questions — Colligative Properties

1. What are colligative properties dependent upon?

A) Chemical nature of the solute

B) Volume of solvent

C) Number of solute particles

D) Color of solute

E) Pressure of the atmosphere

2. Which of the following is not a colligative property?

A) Boiling point elevation

B) Freezing point depression

C) Vapor pressure lowering

D) Density of the solution

E) Osmotic pressure

3. Colligative properties are influenced by:

A) Shape of solute particles

B) Molecular weight of solvent

C) Number of solute particles in solution

D) Type of container

E) Color of the solution

4. Which of the following best defines a colligative property?

A) Depends on type of solute

B) Depends on amount (number) of solute particles

C) Only occurs in non-aqueous solutions

D) Requires electrolytes

E) Is influenced by temperature only

5. The addition of a non-volatile solute to a solvent results in:

A) Increase in vapor pressure

B) Increase in freezing point

C) Increase in boiling point

D) Decrease in solute concentration

E) No change in properties

6. Vapor pressure lowering occurs because:

A) Solute particles increase temperature

B) Solute particles reduce solvent molecules at the surface

C) Solute increases evaporation

D) Solute adds pressure

E) Solvent density increases

7. Boiling point elevation means:

A) The solvent boils at a lower temperature

B) The vapor pressure decreases to zero

C) The boiling point increases due to solute addition

D) The solute evaporates first

E) The solution freezes faster

8. Freezing point depression occurs because:

A) Solute heats the solution

B) Solute particles block ice formation

C) Solvent becomes more viscous

D) Vapor pressure increases

E) Solute reduces atmospheric pressure

9. What is osmotic pressure?

A) The pressure that prevents freezing

B) Pressure applied to evaporate solvent

C) Pressure needed to stop osmosis across a semipermeable membrane

D) Pressure that increases boiling point

E) Pressure due to gas molecules

10. The unit for osmotic pressure is typically:

A) °C

B) atm

C) mol

D) m³

E) kg/mol

11. Which solution will exhibit the greatest colligative effect?

A) 1 m NaCl

B) 1 m glucose

C) 1 m urea

D) 1 m MgCl₂

E) 1 m CH₃OH

12. Which of the following properties will increase when a solute is added to a solvent?

A) Freezing point

B) Vapor pressure

C) Boiling point

D) Solvent volume

E) None of the above

13. Colligative properties depend on:

A) Solute mass

B) Solute molarity

C) Number of dissolved particles (ions or molecules)

D) Solvent polarity

E) Molecular structure

14. Which solution would have the lowest vapor pressure?

A) Pure water

B) 0.1 m NaCl

C) 0.1 m glucose

D) 0.2 m glucose

E) 0.1 m ethanol

15. The freezing point depression constant (Kf) depends on:

A) The solute

B) The solvent

C) The container

D) The gas pressure

E) None of the above

16. A solution that contains a solute that dissociates will have:

A) No effect on colligative properties

B) The same freezing point as the pure solvent

C) Greater colligative effects than a non-electrolyte at the same concentration

D) No boiling point change

E) Lower osmotic pressure

17. Colligative properties are useful in determining:

A) Solvent polarity

B) Molar mass of solutes

C) Solute color

D) Reaction rate

E) Specific heat

18. Which solution would cause the greatest boiling point elevation?

A) 0.1 m NaCl

B) 0.1 m glucose

C) 0.1 m MgCl₂

D) 0.1 m CH₃OH

E) 0.1 m sucrose

19. Which colligative property is most useful for studying cell membranes?

A) Freezing point depression

B) Vapor pressure lowering

C) Osmotic pressure

D) Boiling point elevation

E) Refractive index

20. Colligative properties apply only when:

A) Solute is volatile

B) Solution is saturated

C) Solute is non-volatile and dissolved

D) Temperature is below 0°C

E) Gases are involved

Answer Key with Explanations

1. C – Colligative properties depend on the number of solute particles, not their identity.

2. D – Density is a physical property but not a colligative one.

3. C – Number of solute particles influences colligative effects.

4. B – They depend solely on quantity, not type, of solute particles.

5. C – Boiling point increases because solute lowers vapor pressure.

6. B – Solute particles occupy space at the surface, reducing evaporation.

7. C – The boiling point is raised when solute is added to a solvent.

8. B – Solute disrupts solid lattice formation needed for freezing.

9. C – Osmotic pressure is the pressure needed to stop osmosis.

10. B – It’s usually measured in atmospheres (atm).

11. D – MgCl₂ dissociates into 3 ions, giving stronger effect.

12. C – Only boiling point increases; others decrease.

13. C – The total number of particles (ions or molecules) is what matters.

14. D – 0.2 m glucose has more particles than the other options.

15. B – Kf is a constant for the solvent, not solute.

16. C – Ionic compounds like NaCl dissociate, increasing particle count.

17. B – Used to determine molar mass by freezing point depression.

18. C – MgCl₂ dissociates into 3 particles, increasing boiling point more.

19. C – Osmotic pressure is crucial in understanding cell membrane transport.

20. C – Must be non-volatile solute and properly dissolved in solvent.

Questions on Freezing Point Depression

June 04, 2025 Solutions

Questions on Freezing Point Depression

Multiple-Choice Questions – Freezing Point Depression

1. What is freezing point depression?

A) Increase in the freezing point of a solvent

B) Increase in the temperature of a liquid

C) Decrease in the freezing point of a solvent when a solute is added

D) Boiling of a solution at a lower temperature

E) Melting of solute particles

2. Which of the following best explains freezing point depression?

A) Solute increases the vapor pressure

B) Solute forms stronger bonds with air molecules

C) Solute particles disrupt the formation of a solid lattice

D) Solute lowers boiling point

E) Solute cools the container

3. Freezing point depression is a:

A) Physical constant

B) Chemical change

C) Colligative property

D) Non-colligative property

E) Form of phase separation

4. Which factor does not affect freezing point depression?

A) Nature of solute

B) Concentration of solute

C) Type of solvent

D) Atmospheric pressure

E) Number of solute particles

5. What happens to the freezing point when a solute is added to a pure solvent?

A) It increases

B) It remains unchanged

C) It decreases

D) It becomes zero

E) It turns into the boiling point

6. What is the formula for calculating freezing point depression?

A) ΔTₙ = Kf × m × i

B) ΔTf = Kb × m

C) ΔTf = Kp × V

D) ΔTf = i × R × T

E) ΔTₙ = m × n

7. In the formula ΔTf = Kf × m × i, the symbol Kf stands for:

A) Freezing point temperature

B) Solubility factor

C) Cryoscopic constant of the solvent

D) Volume constant

E) Ionic pressure

8. What does m represent in ΔTf = Kf × m × i?

A) Mass of solute

B) Molar mass of solvent

C) Molality of the solution

D) Mole fraction

E) Molecular number

9. The van’t Hoff factor (i) accounts for:

A) The temperature of freezing

B) The boiling point shift

C) The number of particles the solute dissociates into

D) The solubility rate

E) The vapor pressure

10. Which of the following solutes will cause the greatest freezing point depression per mole?

A) Glucose (C₆H₁₂O₆)

B) NaCl

C) K₂SO₄

D) CH₃OH

E) C₂H₅OH

11. A solution with a higher molality will:

A) Freeze at a higher temperature

B) Boil at a lower temperature

C) Freeze at a lower temperature

D) Be more volatile

E) Have constant freezing point

12. Which of the following is true about the freezing point of salt water compared to pure water?

A) It freezes at a higher temperature

B) It freezes at the same temperature

C) It freezes at a lower temperature

D) It doesn’t freeze

E) It boils more easily

13. Which of the following solvents would likely have the greatest value of Kf?

A) Water

B) Benzene

C) Acetic acid

D) Ether

E) Glycerol

14. What unit is used for the freezing point depression constant (Kf)?

A) °C/mol

B) K/mol

C) °C·kg/mol

D) mol/kg

E) g/mol

15. Why does CaCl₂ lower the freezing point more than NaCl?

A) It dissolves slower

B) It forms fewer ions

C) It is heavier

D) It produces more ions (i = 3)

E) It has a higher Kf

16. Which condition increases the freezing point depression of a solution?

A) Lower molality

B) Non-electrolyte solutes

C) Decrease in solute amount

D) Increase in solute particles

E) Use of volatile solutes

17. What is the freezing point of a 1 molal solution of a non-electrolyte in water? (Kf for water = 1.86 °C·kg/mol)

A) –1.00 °C

B) –0.93 °C

C) –1.86 °C

D) 0 °C

E) +1.86 °C

18. Why is salt often spread on icy roads in winter?

A) To melt the snow chemically

B) To raise the freezing point of water

C) To keep water frozen

D) To lower the freezing point so ice melts

E) To add weight

19. Which solution would have the lowest freezing point?

A) 1 m NaCl

B) 1 m C₆H₁₂O₆

C) 1 m CaCl₂

D) 1 m CH₃OH

E) 1 m sucrose

20. Which of the following causes freezing point depression in a solution?

A) Increase in gas pressure

B) Solute particles preventing crystal formation

C) Increase in solvent density

D) Vapor condensing

E) Boiling of solvent

Answer Key with Full Explanations

1. C – Adding a solute to a solvent causes its freezing point to drop.

2. C – Solute particles interrupt the formation of solid crystals.

3. C – It's a colligative property, depending on solute particle number.

4. D – Atmospheric pressure affects boiling, not freezing point.

5. C – The freezing point is lowered due to solute presence.

6. A – Correct equation for freezing point depression.

7. C – Kf is the cryoscopic constant unique to each solvent.

8. C – m is molality, in mol/kg of solvent.

9. C – The van’t Hoff factor (i) indicates the number of particles after dissociation.

10. C – K₂SO₄ dissociates into 3 ions (2K⁺ and SO₄²⁻), giving highest i.

11. C – More concentrated solution = greater depression in freezing point.

12. C – Salt water freezes below 0°C due to solute effect.

13. A – Water has a relatively high Kf, commonly used as standard.

14. C – Unit for Kf is °C·kg/mol.

15. D – CaCl₂ dissociates into 3 ions (i = 3), NaCl into 2 (i = 2).

16. D – More particles = greater effect on freezing point.

17. C – ΔTf = Kf × m = 1.86 × 1 = 1.86°C depression → freezing point = –1.86°C

18. D – Salt lowers the freezing point, causing ice to melt.

19. C – CaCl₂ dissociates into more particles → greatest depression.

20. B – Solute particles interfere with solidification.

Questions About Vapor Pressure

June 04, 2025 Solutions

Questions About Vapor Pressure

Multiple-Choice Questions – Vapor Pressure: Characteristics and Lowering

1. What is vapor pressure?

A) The pressure required to boil a liquid

B) The pressure of a vapor in equilibrium with its liquid at a given temperature

C) The pressure exerted by a solid

D) The pressure of air over a surface

E) The pressure after condensation

2. Vapor pressure is a property of which phase equilibrium?

A) Gas–solid

B) Solid–liquid

C) Liquid–vapor

D) Gas–plasma

E) Liquid–solid

3. Which factor most directly affects vapor pressure?

A) Altitude

B) Pressure of the container

C) Temperature

D) Solute concentration

E) Surface area

4. As temperature increases, vapor pressure:

A) Decreases

B) Remains constant

C) Increases

D) Drops to zero

E) Becomes undefined

5. A volatile liquid has:

A) Low vapor pressure

B) High boiling point

C) Strong intermolecular forces

D) High vapor pressure

E) Low surface tension

6. Which of the following will have the highest vapor pressure at the same temperature?

A) Water

B) Mercury

C) Ethanol

D) Glycerol

E) Oil

7. The vapor pressure of a solution is generally ________ than that of a pure solvent.

A) Higher

B) Equal

C) Lower

D) Zero

E) Unpredictable

8. What causes the lowering of vapor pressure in a solution?

A) Increased pressure

B) Decreased volume

C) Addition of a non-volatile solute

D) Heating the solvent

E) Removal of solvent

9. Which law explains vapor pressure lowering in ideal solutions?

A) Boyle's Law

B) Henry's Law

C) Dalton’s Law

D) Charles's Law

E) Raoult’s Law

10. According to Raoult's Law, the vapor pressure of a solution is:

A) Equal to that of the solute

B) Proportional to the solute's mole fraction

C) The sum of solvent and solute vapor pressures

D) Proportional to the solvent’s mole fraction

E) Always lower than 1 atm

11. When a non-volatile solute is added to a solvent, what happens to its boiling point?

A) Increases

B) Decreases

C) Stays the same

D) Falls below 0°C

E) Depends on the container

12. What happens to vapor pressure if you add salt to water?

A) It increases

B) It decreases

C) It remains the same

D) It evaporates faster

E) It becomes equal to atmospheric pressure

13. Vapor pressure lowering is a:

A) Colligative property

B) Physical state

C) Chemical reaction

D) Phase transition

E) Type of solution equilibrium

14. Which of the following is not a factor that lowers vapor pressure?

A) Non-volatile solute

B) Increased solute concentration

C) Higher temperature

D) Strong solute–solvent interactions

E) Decreased mole fraction of solvent

15. The vapor pressure of a solution depends on:

A) Type of solute only

B) Solvent only

C) Amount of solute and solvent

D) Molar mass of solute only

E) External pressure only

16. If the vapor pressure of pure water at 25°C is 23.8 mmHg, what happens when a sugar solution is prepared with it?

A) Vapor pressure increases

B) Vapor pressure remains 23.8 mmHg

C) Vapor pressure becomes zero

D) Vapor pressure decreases

E) Vapor pressure depends only on volume

17. Lowering vapor pressure causes which of the following changes in the boiling point?

A) Decreases it

B) Increases it

C) Eliminates it

D) Has no effect

E) Keeps it constant

18. A higher concentration of solute leads to:

A) Higher vapor pressure

B) Lower vapor pressure

C) More evaporation

D) Higher surface tension

E) Increased condensation

19. Which of the following does not describe a volatile substance?

A) Evaporates easily

B) Has low boiling point

C) Has weak intermolecular forces

D) Has low vapor pressure

E) Can form vapor at room temperature

20. Why is vapor pressure important in cooking at high altitudes?

A) Vapor pressure is higher there

B) Water boils at a higher temperature

C) Cooking time is reduced

D) Lower atmospheric pressure lowers boiling point

E) Water cannot vaporize

Answer Key with Full Explanations

1. B – Vapor pressure is the pressure exerted by vapor in equilibrium with its liquid at a given temperature.

2. C – It occurs at the liquid–vapor equilibrium.

3. C – Temperature is the primary factor affecting vapor pressure.

4. C – As temperature increases, molecules escape more easily, increasing vapor pressure.

5. D – A volatile liquid evaporates easily, meaning it has a high vapor pressure.

6. C – Ethanol is more volatile than water and glycerol, so it has a higher vapor pressure.

7. C – Vapor pressure lowers when solutes are added.

8. C – A non-volatile solute reduces the number of solvent molecules at the surface, lowering vapor pressure.

9. E – Raoult’s Law governs vapor pressure lowering in ideal solutions.

10. D – Raoult’s Law: P_solution = X_solvent × P_pure_solvent.

11. A – Lower vapor pressure means the solution must be heated more to boil.

12. B – Adding salt lowers vapor pressure due to reduced surface solvent particles.

13. A – It is a colligative property, depending on solute amount, not type.

14. C – Higher temperature increases vapor pressure, not lowers it.

15. C – It depends on the ratio of solute to solvent, not just one.

16. D – A sugar solution has lower vapor pressure than pure water.

17. B – Lower vapor pressure requires more heat to reach boiling, raising boiling point.

18. B – More solute means fewer solvent molecules at the surface → lower vapor pressure.

19. D – Volatile substances have high, not low, vapor pressure.

20. D – At higher altitudes, lower atmospheric pressure means water boils at a lower temperature.

Questions About Dilution

June 04, 2025 Solutions

Questions About Dilution

Multiple-Choice Questions – Dilution

1. What does the process of dilution involve?

A) Increasing the temperature of a solution

B) Adding more solute to a solution

C) Adding solvent to decrease the solution's concentration

D) Heating the solute

E) Separating the solute from the solvent

2. Which equation is commonly used for dilution calculations?

A) PV = nRT

B) M = mol/L

C) M₁V₁ = M₂V₂

D) C₁ + C₂ = C₃

E) M₁ + M₂ = M₃

3. What happens to the number of moles of solute during dilution?

A) Increases

B) Decreases

C) Doubles

D) Remains the same

E) Becomes zero

4. A 2.0 M solution is diluted from 100 mL to 400 mL. What is the final concentration?

A) 0.25 M

B) 0.5 M

C) 1.0 M

D) 2.0 M

E) 4.0 M

5. A 1.5 M solution is diluted to twice its original volume. What is the new concentration?

A) 3.0 M

B) 1.5 M

C) 0.75 M

D) 0.5 M

E) 1.0 M

6. If 100 mL of a 3.0 M solution is diluted to 300 mL, what is the final molarity?

A) 1.0 M

B) 2.0 M

C) 3.0 M

D) 0.5 M

E) 0.25 M

7. What volume of water should be added to 50 mL of 6.0 M HCl to make a 1.0 M solution?

A) 250 mL

B) 300 mL

C) 350 mL

D) 400 mL

E) 450 mL

8. In the formula M₁V₁ = M₂V₂, M₁ stands for:

A) Final molarity

B) Volume of solvent

C) Initial molarity

D) Moles of solute

E) Molar mass

9. In dilution, which of the following remains constant?

A) Volume

B) Temperature

C) Number of solute particles

D) Concentration

E) Pressure

10. Which action best describes diluting a solution?

A) Evaporating the solvent

B) Adding solute

C) Adding more solution

D) Adding solvent

E) Removing solute

11. A student dilutes 100 mL of 2.0 M NaOH to 200 mL. What is the new concentration?

A) 4.0 M

B) 2.0 M

C) 1.0 M

D) 0.5 M

E) 0.25 M

12. What is the final volume when 20 mL of 5.0 M solution is diluted to 1.0 M?

A) 25 mL

B) 50 mL

C) 75 mL

D) 100 mL

E) 120 mL

13. What is the purpose of dilution in laboratory practice?

A) To increase solution’s temperature

B) To reduce concentration

C) To remove solute

D) To separate components

E) To concentrate a solution

14. A chemist has 10 mL of 6 M HNO₃. How much water is needed to prepare 30 mL of 2 M HNO₃?

A) 10 mL

B) 20 mL

C) 25 mL

D) 30 mL

E) 50 mL

15. Molarity after dilution depends on:

A) Volume of solute

B) Type of solute

C) Final volume only

D) Initial moles and final volume

E) Initial concentration only

16. What is the result of diluting a 0.8 M solution to four times its volume?

A) 0.1 M

B) 0.2 M

C) 0.4 M

D) 0.8 M

E) 1.6 M

17. 25 mL of a 4.0 M solution is diluted to 100 mL. Final molarity is:

A) 0.25 M

B) 1.0 M

C) 2.0 M

D) 3.0 M

E) 4.0 M

18. In M₁V₁ = M₂V₂, what does V₂ represent?

A) Initial volume

B) Final volume

C) Molar mass

D) Total moles

E) Volume of solute only

19. What volume of 10 M HCl is needed to prepare 500 mL of 1 M solution?

A) 10 mL

B) 25 mL

C) 50 mL

D) 100 mL

E) 200 mL

20. A 200 mL solution of 0.5 M is diluted to 1.0 L. What is the new molarity?

A) 0.1 M

B) 0.2 M

C) 0.25 M

D) 0.4 M

E) 0.5 M

Answer Key with Full Explanations

1. C – Dilution decreases concentration by adding solvent, not solute.

2. C – The correct formula is M₁V₁ = M₂V₂.

3. D – The amount of solute remains constant during dilution.

4. B – M₂ = (2.0 M × 100 mL) / 400 mL = 0.5 M.

5. C – Doubling volume halves concentration: 1.5 M → 0.75 M.

6. A – M₂ = (3.0 × 100) / 300 = 1.0 M.

7. D – M₂ = (6.0 × 50) / x = 1.0 → x = 300 mL, water added = 250 mL.

8. C – M₁ = initial molarity.

9. C – Solute amount (moles) does not change during dilution.

10. D – Adding solvent dilutes a solution.

11. C – M₂ = (2.0 × 100) / 200 = 1.0 M.

12. D – V₂ = (5.0 × 20) / 1.0 = 100 mL.

13. B – Dilution reduces concentration for safe or precise handling.

14. B – M₁V₁ = M₂V₂ → 6×10 = 2×x → x = 30 → water = 20 mL.

15. D – Final molarity = moles / final volume.

16. B – 0.8 / 4 = 0.2 M.

17. B – M₂ = (4.0 × 25) / 100 = 1.0 M.

18. B – V₂ is the final volume after dilution.

19. C – 10 × x = 1 × 500 → x = 50 mL.

20. A – M₂ = (0.5 × 200) / 1000 = 0.1 M.

Questions About Molality

June 04, 2025 Solutions

Questions About Molality

Multiple-Choice Questions – Molality

1. What does molality (m) represent?

A) Moles of solute per liter of solvent

B) Moles of solute per kilogram of solvent

C) Moles of solute per gram of solute

D) Grams of solute per kilogram of solvent

E) Moles of solute per milliliter of solution

2. What is the unit of molality?

A) mol/L

B) g/kg

C) mol/kg

D) mol/mL

E) mol/g

3. If 2 moles of NaCl are dissolved in 1 kg of water, what is the molality?

A) 0.5 m

B) 1 m

C) 2 m

D) 3 m

E) 4 m

4. A solution contains 0.5 mol of solute in 0.25 kg of solvent. What is the molality?

A) 0.25 m

B) 0.5 m

C) 1.0 m

D) 2.0 m

E) 4.0 m

5. Which of the following factors does not affect molality?

A) Amount of solute

B) Mass of solvent

C) Volume of solvent

D) Temperature

E) Volume of solution

6. What is the molality if 0.1 mol of solute is dissolved in 200 g of solvent?

A) 0.2 m

B) 0.5 m

C) 1.0 m

D) 2.0 m

E) 5.0 m

7. Which is required to calculate molality?

A) Moles of solute and volume of solution

B) Moles of solute and temperature

C) Moles of solute and mass of solvent

D) Mass of solute and volume of solvent

E) Volume of solution and temperature

8. What is the molality of a solution with 10 g NaOH (molar mass = 40 g/mol) in 500 g of water?

A) 0.25 m

B) 0.5 m

C) 1.0 m

D) 2.0 m

E) 4.0 m

9. What is the molality of a solution with 36 g of glucose (molar mass = 180 g/mol) in 0.2 kg of water?

A) 0.2 m

B) 0.5 m

C) 1.0 m

D) 2.0 m

E) 3.0 m

10. Molality is preferred over molarity when:

A) The solution is very dilute

B) Temperature varies

C) Working with gases

D) Solvent evaporates easily

E) Dealing with pure liquids

11. Which expression correctly defines molality (m)?

A) mol solute / L solution

B) g solute / kg solvent

C) mol solute / kg solvent

D) mol solute / g solvent

E) mol solute × kg solvent

12. What is the molality of a solution prepared with 0.2 mol of solute and 400 g of solvent?

A) 0.2 m

B) 0.4 m

C) 0.5 m

D) 0.8 m

E) 1.0 m

13. A solution contains 5 moles of solute in 2 kg of water. What is its molality?

A) 2.5 m

B) 1.0 m

C) 3.0 m

D) 5.0 m

E) 10.0 m

14. What is the molality of 18 g of H₂O₂ (molar mass = 34 g/mol) dissolved in 0.5 kg of solvent?

A) 0.5 m

B) 1.0 m

C) 1.2 m

D) 2.0 m

E) 2.5 m

15. What mass of solvent (in kg) is needed to prepare a 1 m solution using 2 moles of solute?

A) 0.25

B) 0.5

C) 1

D) 2

E) 3

16. If 0.4 mol of solute is added to 0.2 kg of water, the molality is:

A) 1.0 m

B) 2.0 m

C) 3.0 m

D) 4.0 m

E) 5.0 m

17. Which one of the following is a concentrated solution in terms of molality?

A) 0.01 m

B) 0.1 m

C) 1 m

D) 3 m

E) 0.5 m

18. What is the molality if 1 mole of solute is added to 250 g of solvent?

A) 0.25 m

B) 1.0 m

C) 2.0 m

D) 3.0 m

E) 4.0 m

19. A solution has 0.6 mol of solute and 300 g of solvent. The molality is:

A) 0.5 m

B) 1.0 m

C) 1.5 m

D) 2.0 m

E) 2.5 m

20. In molality calculations, the mass of solvent must be expressed in:

A) Milliliters

B) Kilograms

C) Grams

D) Moles

E) Liters

Answer Key with Full Explanations

1. B – Molality = moles of solute per kilogram of solvent.

2. C – Unit of molality is mol/kg.

3. C – 2 mol / 1 kg = 2 m.

4. D – 0.5 mol / 0.25 kg = 2.0 m.

5. C – Volume is irrelevant to molality.

6. D – 0.1 mol / 0.2 kg = 0.5 m.

7. C – You need moles of solute and mass of solvent (in kg).

8. A – 10 g / 40 = 0.25 mol; 0.25 / 0.5 kg = 0.5 m.

9. B – 36 g / 180 = 0.2 mol; 0.2 / 0.2 kg = 1.0 m.

10. B – Molality is independent of temperature since it’s mass-based.

11. C – Molality = mol solute / kg solvent.

12. C – 0.2 mol / 0.4 kg = 0.5 m.

13. A – 5 mol / 2 kg = 2.5 m.

14. B – 18 / 34 = 0.53 mol ≈ 1.0 m.

15. D – 2 mol / x kg = 1 m → x = 2 kg.

16. B – 0.4 / 0.2 = 2.0 m.

17. D – 3 mol/kg is a high concentration = concentrated.

18. C – 1 mol / 0.25 kg = 4.0 m.

19. C – 0.6 / 0.3 = 2.0 m.

20. B – Solvent must be in kilograms for correct molality.

Questions About Molarity

June 04, 2025 Solutions

Questions About Molarity

Multiple-Choice Questions – Molarity

1. What does molarity (M) represent?

A) Grams of solute per liter of solvent

B) Liters of solution per mole of solute

C) Moles of solute per liter of solution

D) Moles of solute per gram of solution

E) Grams of solute per milliliter of solution

2. Which of the following is the correct unit for molarity?

A) mol/kg

B) g/L

C) mol/L

D) mol/mL

E) L/mol

3. If you dissolve 1 mole of NaCl in 1 liter of water, what is the molarity?

A) 0.5 M

B) 1 M

C) 2 M

D) 0.1 M

E) 10 M

4. To prepare a 0.5 M NaCl solution in 1 liter of water, how many moles of NaCl are needed?

A) 0.25

B) 0.5

C) 1

D) 2

E) 5

5. How many grams of NaCl (molar mass = 58.5 g/mol) are needed to make 2 liters of 1 M solution?

A) 29.25 g

B) 58.5 g

C) 117 g

D) 175.5 g

E) 14.6 g

6. What is the molarity of a solution with 2 moles of solute in 500 mL of solution?

A) 0.25 M

B) 0.5 M

C) 2 M

D) 4 M

E) 1 M

7. If 0.25 moles of KCl are dissolved in 0.5 liters of solution, the molarity is:

A) 0.125 M

B) 0.5 M

C) 1 M

D) 2 M

E) 0.25 M

8. What volume of 2 M solution contains 1 mole of solute?

A) 0.25 L

B) 0.5 L

C) 1 L

D) 2 L

E) 3 L

9. Which combination results in a 1 M solution?

A) 2 moles in 1 L

B) 1 mole in 1 L

C) 1 mole in 2 L

D) 0.5 moles in 0.5 L

E) B and D

10. What happens to molarity if water is added to a solution (dilution)?

A) It increases

B) It remains the same

C) It decreases

D) It doubles

E) It becomes zero

11. What is the molarity if 0.75 moles of solute are dissolved in 1.5 liters of solution?

A) 0.25 M

B) 0.5 M

C) 1 M

D) 2 M

E) 1.5 M

12. What is the molarity of a 500 mL solution containing 49 g of H₂SO₄ (molar mass = 98 g/mol)?

A) 0.25 M

B) 0.5 M

C) 1 M

D) 2 M

E) 4 M

13. To prepare 250 mL of a 0.1 M NaOH solution, how many moles of NaOH are needed?

A) 0.01

B) 0.025

C) 0.05

D) 0.1

E) 0.25

14. Which is not needed to calculate molarity?

A) Volume of solution

B) Mass of solute

C) Temperature

D) Molar mass of solute

E) Amount of solute in moles

15. A solution is made by dissolving 0.2 moles of solute in 400 mL of water. The molarity is:

A) 0.4 M

B) 0.5 M

C) 0.6 M

D) 0.8 M

E) 1.0 M

16. What is the molarity of a solution made by dissolving 12 g of NaOH (molar mass = 40 g/mol) in 500 mL?

A) 0.3 M

B) 0.5 M

C) 0.6 M

D) 1 M

E) 1.5 M

17. If 0.1 moles of HCl are present in 250 mL of solution, the molarity is:

A) 0.1 M

B) 0.25 M

C) 0.4 M

D) 0.5 M

E) 1 M

18. What is the volume required to prepare a 0.2 M solution using 0.1 moles of solute?

A) 100 mL

B) 200 mL

C) 300 mL

D) 400 mL

E) 500 mL

19. Which solution has the highest concentration?

A) 1 mole in 2 L

B) 2 moles in 3 L

C) 0.5 moles in 1 L

D) 2 moles in 1 L

E) 3 moles in 5 L

20. What is the molarity of a solution made with 0.9 g of glucose (molar mass = 180 g/mol) in 100 mL?

A) 0.005 M

B) 0.01 M

C) 0.02 M

D) 0.05 M

E) 0.1 M

Answer Key with Explanations

1. C – Molarity is moles of solute per liter of solution.

2. C – The unit of molarity is mol/L.

3. B – 1 mole in 1 liter = 1 M.

4. B – M = mol/L → mol = 0.5 × 1 = 0.5 mol.

5. C – 2 mol × 58.5 g/mol = 117 g.

6. D – 2 mol / 0.5 L = 4 M.

7. B – 0.25 mol / 0.5 L = 0.5 M.

8. B – 1 mol / 2 M = 0.5 L.

9. E – Both B (1 mol in 1 L) and D (0.5 mol in 0.5 L) give 1 M.

10. C – Adding water dilutes the solution, so molarity decreases.

11. B – 0.75 mol / 1.5 L = 0.5 M.

12. C – 49 g / 98 g/mol = 0.5 mol → 0.5 mol / 0.5 L = 1 M.

13. B – 0.1 M × 0.25 L = 0.025 mol.

14. C – Temperature is not used in the basic molarity formula.

15. B – 0.2 mol / 0.4 L = 0.5 M.

16. C – 12 g / 40 g/mol = 0.3 mol → 0.3 mol / 0.5 L = 0.6 M.

17. B – 0.1 mol / 0.25 L = 0.4 M.

18. E – 0.1 mol / 0.2 M = 0.5 L = 500 mL.

19. D – 2 mol / 1 L = 2 M, the highest.

20. B – 0.9 g / 180 = 0.005 mol → 0.005 mol / 0.1 L = 0.05 M.

Questions on Solubility and Henry's Law of Solubility

June 04, 2025 Solutions

Questions on Solubility and Henry's Law of Solubility

Multiple-Choice Questions – Solubility and Henry’s Law

1. What does solubility describe?

A) The speed at which a substance melts

B) The ability of a solute to conduct electricity

C) The amount of solute that dissolves in a given solvent at a certain temperature

D) The ability of a gas to escape from a liquid

E) The boiling point of a solution

2. Which factor most affects the solubility of a solid in a liquid?

A) Pressure

B) Gravity

C) Temperature

D) Density

E) pH

3. As temperature increases, the solubility of most solid solutes in liquid solvents:

A) Decreases

B) Remains unchanged

C) Increases

D) Becomes zero

E) Turns into gas

4. According to Henry's Law, the solubility of a gas in a liquid is directly proportional to:

A) The volume of the solvent

B) The pressure of the gas above the liquid

C) The mass of the solute

D) The surface area of the container

E) The solute's temperature

5. Which condition will increase the amount of CO₂ dissolved in a soft drink?

A) Heating the soda

B) Decreasing the pressure

C) Shaking the bottle

D) Cooling and sealing under pressure

E) Adding sugar

6. Which type of solute is most affected by pressure?

A) Ionic solids

B) Nonpolar liquids

C) Polar liquids

D) Gases

E) Covalent solids

7. According to Henry's Law, if the pressure of a gas above a liquid doubles, its solubility:

A) Halves

B) Doubles

C) Triples

D) Stays the same

E) Becomes zero

8. The "k" constant in Henry’s Law is dependent on:

A) The pressure of the gas

B) The identity of the gas and the solvent

C) The volume of the container

D) The number of moles of gas

E) The concentration of the solute

9. A gas has a Henry’s Law constant k=3.2×10−2 mol/L\cdotpatmk = 3.2 \times 10^{-2} \, \text{mol/L·atm}k=3.2×10−2mol/L\cdotpatm. If the pressure is 2 atm, what is its solubility?

A) 0.032 mol/L

B) 0.064 mol/L

C) 0.016 mol/L

D) 1.6 mol/L

E) 3.2 mol/L

10. What happens to the solubility of oxygen in water as pressure increases?

A) It increases

B) It decreases

C) It remains unchanged

D) It becomes zero

E) It depends on the solute

11. Why do soda cans "fizz" when opened?

A) The sugar reacts with water

B) The pressure inside is lower than outside

C) Gas solubility decreases as pressure drops

D) Carbonation increases

E) Oxygen rushes in

12. Which of the following decreases gas solubility in liquids?

A) Cooling the solution

B) Increasing gas pressure

C) Heating the solution

D) Decreasing volume

E) Adding salt

13. The units of Henry’s Law constant kkk are typically:

A) atm/mol

B) L/mol

C) mol/L·atm

D) g/mL

E) mol/g

14. When a solution cannot dissolve any more gas under current conditions, it is:

A) Dilute

B) Concentrated

C) Saturated

D) Unsaturated

E) Miscible

15. Which gas is least soluble in water under normal conditions?

A) CO₂

B) NH₃

C) O₂

D) HCl

E) CH₄

16. Henry's Law helps explain why:

A) Solids dissolve faster when crushed

B) Gases dissolve more under high pressure

C) Liquids evaporate faster than gases

D) Salts ionize in water

E) Water freezes at 0°C

17. Deep-sea divers must ascend slowly because:

A) Temperature increases with depth

B) They lose body heat rapidly

C) Henry's Law means dissolved gases will come out of solution if pressure drops quickly

D) Water density changes

E) Salts accumulate in tissues

18. Which is not an application of Henry’s Law?

A) Carbonated beverages

B) Breathing under pressure

C) Scuba diving safety

D) Crystallization of salts

E) Gas exchange in lungs

19. What factor would not significantly change the solubility of a solid in water?

A) Temperature

B) Stirring

C) Surface area

D) Pressure

E) Nature of solvent

20. In Henry’s Law, the equation C=kPC = kPC=kP represents:

A) Concentration equals rate times time

B) Pressure equals constant divided by volume

C) Solubility equals constant times gas pressure

D) Moles equals concentration divided by pressure

E) Temperature equals pressure times solubility

Questions on Solubility and Henry's Law of Solubility

Answer Key with Explanations

1. C – Solubility is the maximum amount of solute that dissolves in a solvent at a specific temperature.

2. C – Temperature is a major factor in the solubility of solids in liquids.

3. C – Solubility of most solids increases with higher temperature.

4. B – Henry’s Law states solubility of a gas is proportional to its pressure.

5. D – Cooling and high pressure increase CO₂ solubility in soda.

6. D – Gases are highly pressure-sensitive due to their compressibility.

7. B – If pressure doubles, gas solubility doubles (linear relationship).

8. B – The constant k depends on the gas and solvent pair.

9. B – C=kP=0.032×2=0.064 mol/LC = kP = 0.032 \times 2 = 0.064 \, \text{mol/L}C=kP=0.032×2=0.064mol/L

10. A – Increasing pressure increases oxygen’s solubility in water.

11. C – When the can is opened, pressure drops, and gas escapes.

12. C – Heating a solution causes gas to escape, lowering solubility.

13. C – Henry’s Law constant typically has units of mol/L·atm.

14. C – A solution that can’t hold more gas is saturated.

15. E – Methane (CH₄) is the least soluble in water (nonpolar).

16. B – Henry’s Law explains why gases dissolve better under pressure.

17. C – Fast pressure drop causes dissolved gases to form bubbles in blood (the bends).

18. D – Salt crystallization is unrelated to Henry’s Law (not gas-related).

19. D – Pressure has little effect on solid solubility.

20. C – Henry’s Law: C=kPC = kPC=kP, where C = solubility, P = pressure, k = constant.

Questions on Saturated and Unsaturated Solutions

June 04, 2025 Solutions

Questions on Saturated and Unsaturated Solutions

Multiple-Choice Questions – Saturated and Unsaturated Solutions

1. What is a saturated solution?

A) A solution with no solute

B) A solution that can still dissolve more solute

C) A solution with undissolved particles

D) A solution holding the maximum amount of solute at a given temperature

E) A solution with only one component

2. What happens if more solute is added to a saturated solution?

A) It dissolves easily

B) It increases the volume

C) It evaporates

D) It crystallizes or settles at the bottom

E) It changes the color of the solvent

3. What is an unsaturated solution?

A) A solution that cannot dissolve any more solute

B) A solution with more solute than solvent

C) A solution that contains less solute than it can dissolve

D) A supersaturated solution

E) A heterogeneous mixture

4. If a solution still dissolves more solute, it is:

A) Saturated

B) Supersaturated

C) Colloidal

D) Dilute

E) Unsaturated

5. What best describes a supersaturated solution?

A) A solution with zero solute

B) A solution that is at equilibrium

C) A solution with more dissolved solute than normally possible

D) A solid mixture

E) A gaseous solution

6. Which factor increases solubility in most solid-liquid solutions?

A) Decreasing temperature

B) Stirring slowly

C) Lowering pressure

D) Increasing temperature

E) Removing the solvent

7. Which of the following is a sign of saturation in a solution?

A) All solute is dissolved

B) The solvent is colored

C) The solution is boiling

D) Undissolved solute is visible

E) The solution is very dilute

8. Which solution holds less than the maximum amount of solute?

A) Supersaturated

B) Saturated

C) Homogeneous

D) Unsaturated

E) Concentrated

9. When no more solute can be dissolved, the solution is:

A) Diluted

B) Supersaturated

C) Saturated

D) Miscible

E) Polar

10. How can a supersaturated solution be formed?

A) Cooling a saturated solution carefully

B) Adding more solvent to a saturated solution

C) Boiling an unsaturated solution

D) Filtering a saturated solution

E) Shaking a solvent rapidly

11. A saturated solution at a given temperature becomes unsaturated when:

A) Pressure is increased

B) More solute is added

C) The solution is heated

D) The solute is removed

E) It is frozen

12. Which of the following is always true about an unsaturated solution?

A) It contains more solute than solvent

B) It can dissolve more solute

C) It is unstable

D) It will always become supersaturated

E) It is at equilibrium

13. Which factor does not affect whether a solution is saturated?

A) Temperature

B) Type of solute

C) Volume of container

D) Amount of solvent

E) Amount of solute

14. What happens when a saturated solution is cooled and becomes supersaturated?

A) The solute dissolves faster

B) The solution separates

C) Excess solute may crystallize

D) All solute evaporates

E) Nothing changes

15. Which of these is most likely to form a supersaturated solution?

A) Cold water with sugar

B) Room-temperature water with salt

C) Hot water slowly cooled with extra solute

D) Water and oil mixture

E) Any saturated solution

16. A solution that looks clear but forms crystals when disturbed is likely:

A) Saturated

B) Dilute

C) Supersaturated

D) Unsaturated

E) A colloid

17. Which statement about saturated solutions is correct?

A) They contain no solute

B) They are always visible as solids

C) They hold more solute than possible

D) They are at equilibrium between dissolved and undissolved solute

E) They are always unstable

18. If no solute is visible and more solute still dissolves, the solution is:

A) Supersaturated

B) Saturated

C) Unsaturated

D) Concentrated

E) Colloidal

19. Which of the following might happen when a seed crystal is added to a supersaturated solution?

A) The solute disappears

B) The temperature rises

C) Crystals form quickly

D) The solution becomes unsaturated

E) Nothing changes

20. Which tool can help determine whether a solution is saturated?

A) pH meter

B) Thermometer

C) Conductivity tester

D) Adding more solute and observing

E) Graduated cylinder

Questions on Saturated and Unsaturated Solutions

Answer Key with Explanations

1. D – A saturated solution contains the maximum solute that can dissolve at a given temperature.

2. D – Extra solute in a saturated solution will settle at the bottom or crystallize.

3. C – An unsaturated solution can still dissolve more solute.

4. E – If more solute can dissolve, the solution is unsaturated.

5. C – A supersaturated solution holds more solute than normal, under special conditions.

6. D – For most solids, raising the temperature increases solubility.

7. D – Undissolved solute indicates that the solution is saturated.

8. D – An unsaturated solution holds less solute than it can.

9. C – A saturated solution cannot dissolve more solute under the same conditions.

10. A – Supersaturated solutions are made by cooling saturated solutions slowly without disturbing them.

11. C – Heating increases solubility, making a saturated solution unsaturated again.

12. B – Unsaturated solutions can still accept and dissolve more solute.

13. C – The volume of the container has no direct effect on saturation unless it affects solvent amount.

14. C – Cooling may lead to excess solute crystallizing out.

15. C – Supersaturation requires dissolving solute at high temperature, then cooling slowly.

16. C – A supersaturated solution may crystallize if disturbed.

17. D – Saturated solutions are at dynamic equilibrium between dissolved and undissolved solute.

18. C – If solute still dissolves, the solution is unsaturated.

19. C – A seed crystal triggers rapid crystallization in a supersaturated solution.

20. D – Adding more solute is a practical test: if it doesn’t dissolve, the solution is saturated.

Questions on Solute-Solvent Combinations

June 04, 2025 Solutions

Questions on Solute-Solvent Combinations

Multiple-Choice Questions – Solute-Solvent Combinations

1. In a sugar water solution, what is the solute?

A) Water

B) Sugar

C) Both water and sugar

D) Neither

E) Oxygen

2. In which of the following is the solvent a gas?

A) Soda water

B) Brass

C) Air

D) Vinegar

E) Sugar solution

3. Which pair is an example of solid solute in liquid solvent?

A) Oxygen in water

B) Salt in water

C) Milk

D) Air

E) Alcohol in water

4. What is the solvent in seawater?

A) Salt

B) Water

C) Sand

D) Minerals

E) Chlorine

5. Which is a correct example of gas solute in liquid solvent?

A) Air

B) Oxygen in water

C) Salt in water

D) Alcohol in water

E) Gold in mercury

6. In a solution of carbon dioxide in water, which is the solute?

A) Carbon dioxide

B) Water

C) Both

D) Neither

E) Hydrogen

7. Which of these is a liquid-liquid solution?

A) Sugar in tea

B) Alcohol in water

C) Smoke

D) Fog

E) Ice cream

8. Which is an example of solid-solid solution?

A) Brass

B) Vinegar

C) Milk

D) Soda

E) Cloud

9. What kind of solution is oxygen in nitrogen (air)?

A) Solid in gas

B) Gas in gas

C) Gas in liquid

D) Liquid in gas

E) Solid in solid

10. What type of solute-solvent combination is amalgam (e.g., silver in mercury)?

A) Gas in gas

B) Liquid in liquid

C) Solid in liquid

D) Solid in gas

E) Liquid in solid

11. In vinegar, acetic acid is the:

A) Solute

B) Solvent

C) Colloid

D) Suspension

E) Emulsion

12. What is the solvent in rubbing alcohol (isopropanol + water)?

A) Isopropanol

B) Water

C) Alcohol

D) Both equally

E) Depends on proportion

13. In a gaseous solution, which component is usually the solvent?

A) The more dense gas

B) The less reactive gas

C) The gas in lower amount

D) The gas in greater amount

E) The gas that dissolves

14. Which of the following is not a possible solute-solvent combination?

A) Gas in gas

B) Solid in gas

C) Liquid in solid

D) Liquid in gas

E) All are possible

15. What happens when two liquid substances form a solution and mix in all proportions?

A) They are immiscible

B) They are a colloid

C) They are said to be miscible

D) One is always a gas

E) One solidifies

16. In which combination is the solute a gas and the solvent a solid?

A) Hydrogen in palladium

B) Oxygen in water

C) Helium in air

D) Ammonia in alcohol

E) Carbon dioxide in soda

17. Which combination is best described as solid dispersed in gas?

A) Fog

B) Smoke

C) Milk

D) Steel

E) Soda water

18. Which term applies to two liquids that do not form a solution?

A) Miscible

B) Homogeneous

C) Soluble

D) Immiscible

E) Saturated

19. Which of these combinations represents a liquid solute in solid solvent?

A) Milk

B) Fog

C) Gel

D) Amalgam

E) Salt solution

20. In soda water, which is the solvent?

A) Sugar

B) Water

C) Carbon dioxide

D) Oxygen

E) Ethanol

Questions on Solute-Solvent Combinations

Questions About Solutions

Answers and Explanations

1. B – Sugar is the solute (the substance being dissolved), water is the solvent.

2. C – Air is a gas solution (mainly nitrogen as solvent, oxygen as solute).

3. B – Salt in water is a classic solid-liquid solution.

4. B – Water is the solvent in seawater; salt and other minerals are solutes.

5. B – Oxygen dissolved in water is a gas solute in liquid solvent.

6. A – In carbonated drinks, carbon dioxide (gas) is the solute.

7. B – Alcohol in water is a liquid-liquid solution.

8. A – Brass is a solid-solid solution (copper + zinc).

9. B – Air is a gas-gas solution (oxygen dissolved in nitrogen).

10. C – Amalgam is a solid (e.g., silver) dissolved in mercury (liquid).

11. A – Acetic acid is the solute in vinegar (solvent = water).

12. E – The solvent depends on which component is in greater quantity.

13. D – In gas-gas solutions, the component in greater amount is the solvent.

14. E – All listed combinations are possible.

15. C – When two liquids mix in all proportions, they are said to be miscible.

16. A – Hydrogen in palladium is gas solute in solid solvent.

17. B – Smoke is a solid dispersed in gas (aerosol-type mixture).

18. D – Two liquids that do not mix form an immiscible pair (e.g., oil + water).

19. D – Amalgam (liquid mercury + solid metal) is liquid in solid.

20. B – In soda water, water is the solvent, carbon dioxide is the solute.

Questions About Solutions

June 04, 2025 Solutions

Questions About Solutions

Multiple-Choice Questions – Solutions

1. What is a solution?

A) A pure substance

B) A heterogeneous mixture

C) A homogeneous mixture of two or more substances

D) A compound

E) A chemical element

2. In a saltwater solution, the salt is the:

A) Solvent

B) Colloid

C) Solute

D) Suspension

E) Precipitate

3. Which of the following is not a characteristic of a solution?

A) Particles do not settle

B) Homogeneous throughout

C) Can be filtered easily

D) Particles are very small

E) Appears uniform

4. Which is the most common solvent in everyday life?

A) Ethanol

B) Acetone

C) Benzene

D) Water

E) Ammonia

5. What is the solute in carbonated water?

A) Water

B) Carbon dioxide

C) Sugar

D) Nitrogen

E) Oxygen

6. Which of the following is not a type of solution?

A) Gas in gas

B) Liquid in liquid

C) Solid in gas

D) Solid in solid

E) Gas in solid

7. Which of the following is an example of a solid solution?

A) Seawater

B) Air

C) Steel

D) Soda

E) Milk

8. What term describes how much solute can dissolve in a solvent at a specific temperature?

A) Concentration

B) Solubility

C) Molarity

D) Molality

E) Dilution

9. What happens to most solid solutes as temperature increases?

A) Solubility decreases

B) Solubility remains the same

C) Solubility increases

D) Solubility becomes zero

E) They evaporate

10. A solution that contains the maximum amount of solute at a given temperature is:

A) Dilute

B) Unsaturated

C) Supersaturated

D) Saturated

E) Concentrated

11. What happens in a supersaturated solution if more solute is added?

A) It evaporates

B) The solution boils

C) Crystals form

D) The solute dissolves

E) Nothing happens

12. Which of the following is a gaseous solution?

A) Steel

B) Sugar water

C) Vinegar

D) Air

E) Oil

13. Which method will not increase the rate at which a solute dissolves in a solvent?

A) Stirring

B) Heating

C) Crushing the solute

D) Using a smaller container

E) Increasing surface area

14. What is a concentrated solution?

A) A solution with no solute

B) A solution that is saturated

C) A solution with a large amount of solute

D) A mixture of two solids

E) A solution with particles visible to the eye

15. Which of the following best describes a dilute solution?

A) Contains mostly solute

B) Contains a small amount of solute

C) Cannot dissolve more solute

D) Has undergone filtration

E) Is a solid at room temperature

16. What type of solution is vinegar?

A) Solid in solid

B) Gas in gas

C) Liquid in liquid

D) Solid in gas

E) Gas in liquid

17. What determines whether a substance will dissolve in a given solvent?

A) Particle size

B) Color

C) Density

D) “Like dissolves like” principle

E) Electrical conductivity

18. In which of the following are electrolytes typically found?

A) Distilled water

B) Sugar solution

C) Saltwater

D) Alcohol

E) Olive oil

19. What unit is often used to express solution concentration?

A) Grams

B) Liters

C) Moles

D) Molarity (mol/L)

E) Celsius

20. A solution that can still dissolve more solute is called:

A) Saturated

B) Supersaturated

C) Dilute

D) Concentrated

E) Unsaturated

Answers with Explanations

1. C – A solution is a homogeneous mixture of two or more substances.

2. C – The solute is the substance being dissolved, in this case, salt.

3. C – Solutions cannot be filtered easily, because the particles are too small.

4. D – Water is the most universal and common solvent.

5. B – Carbon dioxide is the gas dissolved in water in carbonated drinks.

6. C – Solid in gas is not a typical solution; it is more like a suspension.

7. C – Steel is a solid solution of carbon in iron.

8. B – Solubility is the maximum amount of solute that can dissolve in a solvent.

9. C – Increasing temperature generally increases solubility for solids in liquids.

10. D – A saturated solution holds the maximum solute at a given temperature.

11. C – Adding more solute to a supersaturated solution usually causes crystallization.

12. D – Air is a gaseous solution (mainly nitrogen with oxygen and others mixed in).

13. D – Using a smaller container won’t help dissolve solute faster.

14. C – A concentrated solution contains a large amount of solute.

15. B – A dilute solution has little solute compared to solvent.

16. C – Vinegar is acetic acid dissolved in water, a liquid-liquid solution.

17. D – The phrase "like dissolves like" means polar solutes dissolve in polar solvents, and nonpolar in nonpolar.

18. C – Saltwater conducts electricity because salt dissociates into ions (electrolytes).

19. D – Molarity is the standard unit: mol of solute per liter of solution.

20. E – An unsaturated solution can still dissolve more solute.