Abstract
We used apples pieces that were placed in five different cups with different amounts of molar concentrations of sucrose. We recorded the initial mass and the final mass after we left the pieces in the cups overnight.
Purpose: The purpose of this experiment is to understand how water potential works by determining the water potential of apple cells.
Background: The measure of the relative tendency of water to move from one area to another, and is commonly represented by the Greek letter Ψ (Psi). Water potential is caused by osmosis, gravity, mechanical pressure, or matrix effects including surface tension. It is useful in understanding water movements within plants, animals, and soil. * http://www.biology-online.org/dictionary/Water_potential
Hypothesis: We predicted that if we put .2m of sucrose in distilled water, then the final mass of the apples will decrease.
Materials/ Equipment used: * 6 250-mL beakers * Sucrose solution * Cork borer * Apples * balance * Paper towel * Plastic wrap * Knife
Procedure:
1. Pour 100 mL of the assigned solution into a labeled 250 mL beaker. Slice an apple into discs that are approximately 3cm thick. 2. Use the cork borer (approx. 5 mm in inner diameters) to cut 24 apple cylinders. Don’t include the skin of the apple. You need four apple pieces for each beaker. 3. Keep your apple cylinders covered in a beaker until it is your turn to use the balance. 4. Record the initial mass of the four cylinders together and then put them into one of the beakers with the sucrose solution. (Repeat until all sucrose solutions have four apple cylinders in them). 5. Cover the beakers with plastic wrap to prevent evaporation. 6. Let stand over night 7. Remove the pieces from the beakers, blot with paper towels and record final mass.
Data Collected: (A) Contents in beaker | Initial Mass | Final Mass | Mass Difference (%) | % change in mass