Osmosis and diffusion are chemical phenomena occurring due to differences in concentration. The particles move from a higher concentration region to a low concentration region in diffusion. In contrast, in osmosis, the particles move from a lower concentration region to a high concentration region.
| Definition: Diffusion refers to the movement of particles from high concentration to low concentration. In contrast, osmosis refers to the movement of particles from low concentration to high concentration through a semi-permeable membrane. |
Q1. The passage of water across a selectively permeable membrane is known as
(c) Facilitated diffusion
(d) None of the above
Answer: (a) The passage of water across a selectively permeable membrane is known as osmosis.
Q2. Which of the following solutions contains a low solute concentration relative to another solution?
(a) Hypotonic solution
(b) Isotonic solution
(c ) Hypertonic solution
(d) None of the above
Answer: (a) A hypotonic solution contains a low concentration of solute relative to another solution.
Q3. Reverse osmosis is also known as
(b) Hyper osmosis
(c ) Double osmosis
(d) None of the above
Answer: (a) Reverse osmosis is also known as hyperfiltration.
Q4. Transpiration is a phenomenon pertaining to
(c) Facilitated diffusion
(d) None of the above
Answer: (a) Transpiration is a phenomenon pertaining to diffusion.
Q5. Which of the following phenomena is responsible for raisins’ swelling in water?
(d) None of the above
Answer: Endosmosis is responsible for the swelling of raisins in water.
Q6. What is diffusion?
Answer: Diffusion refers to the movement of particles from high concentration to low concentration.
Example: The smell of food cooked in the kitchen diffuses in the entire house is an example of diffusion that we encounter in everyday life. Moreover, perfume fragrance also spreads throughout the room. It is also an example of diffusion.
Q7. What is Graham’s law of diffusion?
Answer: Graham’s law of diffusion states that the rate of diffusion of gases is inversely proportional to the square roots of their densities. It is applicable only to gases.
Q8. What is osmosis?
Answer: Osmosis refers to the movement of particles from low concentration to high concentration through a semi-permeable membrane.
Example: Absorption of water from the soil and swelling of raisins when placed in water are examples of osmosis that we encounter in everyday life.
Q9. What are the various factors that affect the rate of osmosis?
Answer: Various factors that affect the rate of osmosis are mentioned below.
4. Concentration gradient
5. Water Potential
Q10. What is osmotic pressure?
Answer: Osmotic pressure refers to the minimum pressure that must be applied to stop osmosis, i.e. the movement of particles from low concentration to high concentration through a semi-permeable membrane.
π = Osmotic Pressure
i = Vant Hoff factor
C = Molar concentration of the solute
R = Gas Constant
It depends on the molar concentration of the solute particles in the solution and the surrounding temperature.
Q11. What is an osmotic solution?
Answer: A solution with the tendency and power to perform osmosis is known as an osmotic solution. We can classify osmotic solutions into three kinds.
1. Isotonic solution
2. Hypertonic Solution
3. Hypotonic Solution
Q12. What are isotonic, hypertonic and hypotonic solutions?
Answer: Isotonic Solutions: An isotonic solution is a solution that has an equal concentration of solutes inside and outside the cell.
Hypertonic Solutions: A hypertonic solution is a solution that has a high concentration of solute outside the cell than inside.
Hypotonic Solutions: A hypotonic solution is a solution that has a high concentration of solute inside the cell than outside.
Q13. What are the different types of osmosis?
Answer: We can classify osmosis into two types, i.e.
1. Endosmosis: Endosmosis occurs when a substance is placed in a hypotonic solution, where the solute concentration is more inside the cell than outside. The solvent molecules will move inside the cell in a hypotonic solution, and the cell will become more turgid or undergo deplasmolysis.
2. Exosmosis: Exosmosis occurs when a substance is placed in a hypertonic solution, where the solute concentration is less inside the cell than outside. The solvent molecules will move outside of the cell in a hypertonic solution, and the cell will become more flaccid or undergo plasmolysis.
Q14. What are the various factors that affect the rate of diffusion?
Answer: Various factors that affect the rate of diffusion are mentioned below.
2. Size of the Particle
3. Area of Interaction
4. Concentration gradient steepness
Q15. Match the following.
| Column I | Column II |
|---|---|
| Diffusion | Hydrophite substances. |
| Osmosis | Shrinkage protoplasm. |
| Imbibition | Semipermeable membrane. |
| Plasmolysis | Free movement of ions and gases. |
Answer:
| Column I | Column II |
|---|---|
| Diffusion | Free movement of ions and gases. |
| Osmosis | Semipermeable membrane. |
| Imbibition | Hydrophite substances. |
| Plasmolysis | Shrinkage protoplasm. |
Q1. Differentiate between osmosis and diffusion.
Q2. What is reverse osmosis?
Q3. Give some examples of osmosis that we encounter in everyday life?
Q4. What is dialysis?
Q5. Explain different types of diffusion.
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