Unit 6: Solutions

What are Solutions?

The study of Solutions focuses on understanding how substances dissolve to form homogeneous mixtures known as solutions. This unit explores the components of solutions, including solutes and solvents, and examines the factors that affect solubility and concentration. Students learn about different types of solutions, their properties, and how they are used in various applications, from everyday products to industrial processes.

Key Topics in Solutions:

• Components of Solutions: Understanding solutes (substances dissolved) and solvents (substances doing the dissolving) in a solution.
• Types of Solutions: Exploring different kinds of solutions, including gaseous, liquid, and solid solutions.
• Solubility: Examining factors that affect solubility, such as temperature, pressure, and the nature of solutes and solvents.
• Concentration: Learning how to measure and express concentration using units like molarity, molality, and percent composition.
• Colligative Properties: Studying properties that depend on the number of solute particles, including boiling point elevation and freezing point depression.

Benefits of Studying Solutions:

• Practical Knowledge: Provides essential understanding of how substances interact and mix, relevant to everyday life and various industries.
• Application Skills: Enhances ability to prepare and analyze solutions, crucial for fields such as chemistry, medicine, and environmental science.
• Scientific Insight: Builds a foundation for understanding chemical reactions and processes that involve solutions.

This unit is key for students to comprehend the nature of solutions, their preparation, and their properties. Mastery of these concepts is essential for practical applications in chemistry and other scientific disciplines.

1. Mist is an example of solution:

a. Liquid in gas
b. Gas in liquid
c. Solid in gas
d. Gas in solid

2. Which one of the following is a ‘liquid in solid’ solution?

a. Sugar in water
b. Butter
c. Opal
d. Fog

3. Concentration is a ratio of

a. Solvent to solute
b. Solute to solution
c. Solvent to solution
d. Both a and b

4. Which one of the following solutions contains more water?

a. 2 M
b. 1 M
c. 0.5 M
d. 0.25 M

5. A 5 percent (w/w) sugar solution means that:

a. 5 g of sugar is dissolved in 90 g of water
b. 5 g of sugar is dissolved in 100 g of water
c. 5 g of sugar is dissolved in 105 g of water
d. 5 g of sugar is dissolved in 95 g of water

6. If the solute-solute forces are strong enough than those of solute – solvent
forces. The solute:

a. Dissolves readily
b. Does not dissolve
c. Dissolve slowly
d. Dissolves and precipitates

7. Which one of the following will show negligible effect of temperature on
its solubility?

a. KCl
b. KNO₃
c. NaNO₃
d. NaCl

8. Which one of the following is heterogeneous mixture?

a. Milk
b. Ink
c. Milk of magnesia
d. Sugar solution

9. Tyndall effect is shown by:

a. Sugar solution
b. Paints
c. Jelly
d. Chalk solution

10. Tyndall effect is due to:

a. Blockage of beam of light
b. Non-scattering of beam of light
c. Scattering of beam of light
d. Passing through beam of light

11. If 10 cm³ of alcohol is dissolved in 100 g of water, it is called:

a. % w/w
b. % w/v
c. % v/w
d. % v/v

12. When a saturated solution is diluted it turns into:

a. Supersaturated solution
b. Unsaturated solution
c. A concentrated solution
d. None of these

13. Molarity is the number of moles of solute dissolved in:

a. 1kg of solution
b. 100g of solvent
c. 1 dm³ of solvent
d. 1 dm³ of solution