Osmosis

• What is isotonic?


  The same concentration.
• What is osmosis?

  Diffusion of water through a membrane
• What type of solution has a high concentration of water molecules?


  Dilute solution
• What type of solution has a low concentration of water molecules?


  Concentrated solution
• From where does water move during osmosis?

  From a dilute solution to a concentrated solution
• What is the role of a partially permeable membrane in osmosis?


  It allows water to pass but not solutes
• What are the types of solutions mentioned in osmosis?

  • Pure solution
  • Dilute solution
  • Concentrated solution
• What are the characteristics of dilute and concentrated solutions?

  • Dilute solutions: High water concentration
  • Concentrated solutions: Low water concentration
• Semipermeable membrane

  A selectively permeable membrane that allows certain substances, such as water molecules, to pass through, while restricting the passage of other substances.
• What is the plant tissue used in the osmosis experiment?

  Potato
• Why is it important to use potato cylinders of the same diameter?

  To compare results more easily
• How many potato cylinders are prepared for the experiment?

  Three
• What is the purpose of removing the potato skin?

  It is impermeable to water
• What length should the potato cylinders be cut to?

  Three centimeters
• Why is it necessary to measure the length and mass of the potato cylinders?

  To record changes due to osmosis
• What type of balance is used to measure the mass of the potato cylinders?

  Top pan balance
• Why is a high-resolution balance used in the experiment?

  To detect small changes in mass
• What is the first solution added to the boiling tube?

  Distilled water
• What is the purpose of labeling the boiling tubes?

  To avoid mixing up samples
• What is added to the distilled water to prevent evaporation?

  A bung
• What concentrations of sucrose solutions are used in the experiment?

  0.25 molar and 0.5 molar
• Why were samples prepared 24 hours in advance?

  To allow for better results
• What happens to the potato cylinder in distilled water after 24 hours?

  It increases in length and mass
• How much did the length of the potato cylinder in distilled water increase?

  Two millimeters
• What was the mass of the potato cylinder after being in distilled water?

  3.12 grams
• What was the result for the potato cylinder in the 0.25 molar sucrose solution?

  Small increase in mass
• What was the mass of the potato cylinder after being in the 0.25 molar sucrose solution?

  3.06 grams
• What happened to the potato cylinder in the 0.5 molar sucrose solution?

  It decreased in mass
• What was the mass of the potato cylinder after being in the 0.5 molar sucrose solution?

  2.62 grams
• What is the calculation needed to find the difference in mass?

  Final mass minus initial mass
• What is the formula for calculating percentage change in mass?

  Change in mass divided by initial mass
• What does a negative percentage change indicate?

  Decrease in mass
• What are the expected results of the osmosis experiment with varying sucrose concentrations?

  • Distilled water: Increase in mass
  • 0.25 molar sucrose: Small increase in mass
  • 0.5 molar sucrose: Decrease in mass
• What is the relationship between sucrose concentration and potato mass?

  • Higher sucrose concentration leads to:
  • Decreased mass in potato
  • Lower water concentration in potato
• What is osmosis?

  • Movement of water across a semi-permeable membrane
  • From low solute concentration to high solute concentration