Topic 1 - Core Practical: Osmosis In Potatoes And Percentage Gain And Loss Of Mass Flashcards
What is the first step in measuring percentage gain or loss of mass using potato disks?
Cut potato into small discs of equal size (e.g., 2cm diameter)
Equal size ensures uniformity in the experiment.
What must be done to the potato disks before measuring their initial mass?
Blot the potato disks gently with tissue paper to remove excess water
This helps to ensure accurate mass measurements.
What is the formula for calculating percentage change in mass?
(change in mass / start mass) x 100
This equation helps quantify the gain or loss of mass in the experiment.
What is the independent variable in the osmosis experiment with potato disks?
Concentration of the sucrose solution
This is the variable that is deliberately changed during the experiment.
What is the dependent variable in the osmosis experiment with potato disks?
Change in mass of the potato disks
This variable is measured to see how it responds to changes in the independent variable.
What is a control variable in the osmosis experiment?
Diameter of the potato disks (2cm)
Keeping this constant ensures that differences in mass change are due to the sucrose concentration.
What is happening to water in the osmosis experiment with potato disks?
Water is moving by osmosis from a more dilute solution (in the potato) to a more concentrated solution (the sucrose solution)
This movement occurs across a selectively permeable membrane.
True or False: The potato disks are placed in sucrose solutions of the same concentration in the osmosis experiment.
False
The disks are placed in sucrose solutions of different concentrations.
Fill in the blank: The percentage change in mass must be recorded as a _______.
percentage (%)
This indicates the proportional change in mass relative to the starting mass.
