B1- osmosis

• What is osmosis?

  Osmosis is the passive movement of water particles through a partially permeable membrane.
• What is a partially permeable membrane?

  A partially permeable membrane has very small holes that allow only small molecules, like water, to pass through.
• How do water molecules behave during osmosis?

  Water molecules move randomly and pass both ways through the membrane during osmosis.
• Why is there a net flow of water into the region with fewer water molecules during osmosis?

  There is a net flow because there are more water molecules on one side than the other.
• What happens to the concentration of the stronger solution during osmosis?

  The stronger solution becomes more dilute as water moves into it.
• How is osmosis related to diffusion?

  Osmosis is a type of diffusion specifically involving the passive movement of water particles.
• What is the procedure to observe osmosis using potato cylinders?

  1. Cut potato into identical cylinders.
  2. Place cylinders in beakers with different sugar solutions (e.g., pure water, 1 mol/dm³).
  3. Measure initial mass of cylinders.
  4. Leave cylinders in solutions for 24 hours.
  5. Dry and measure final mass.
  6. Calculate percentage change in mass.
• What is the dependent variable in the osmosis experiment with potato cylinders?

  The dependent variable is the mass of the potato cylinders.
• What is the independent variable in the osmosis experiment with potato cylinders?

  The independent variable is the concentration of the sugar solution.
• What factors must be controlled to ensure a fair test in the osmosis experiment?

  • Volume of solution
  • Temperature
  • Time
  • Type of sugar used
• What errors should be considered when conducting the osmosis experiment?

  Errors may arise from not fully drying potato cylinders or evaporation of water from beakers.
• How can the effects of errors in the osmosis experiment be minimized?

  By repeating the experiment and calculating a mean percentage change at each concentration.