Osmosis
Osmosis & Osmotic Concentration
Osmosis & Osmotic Concentration
Research Question: What is the osmotic concnetration of specific plant tissues?
Research Question: What is the osmotic concnetration of specific plant tissues?
Prepare Solutions
- Make 2 liter of stock solution of 1M sucrose (C12H22O11) solution. Use can use the Molecular weight calculator to determine the molecular weight.
- Using this stock solution, make 200ml with the following concentrations: 0.8M, 0.6M,0.4M, and 0.2M.
Collect and Analyze your data
- Cut six (6) 8-cubic centimeter (2 cm X 2 cm X 2 cm) blocks from a potato. The blocks should not include the skin. You can approximate the size, but make sure that it is small enough to be submerged in the containers you are provided with.
- Enter the mass of each cube in the data sheet
- Place one potato cube in each of the following solutions: 1.0M, 0.8M, 0.6M, 0.4M, 0.2M, and 0.0M sucrose
- Determine the mass of each cube near the end of the period. and enter the value in the data sheet.
- Graph the percent change in mass as a function of time.
- Estimate the osmotic concentration of the potato tissue by determining the average molarity of solution at which there is no change in mass.
- Enter your estimate in the quickwrite as directed by your instructor.
- Repeat the process for celery, using dimensions of your choice.
Analyze the class data
- Examine a plot of the class data of percent change in mass as a function of time.
- Estimate the osmotic concentration of potato tissue from whole class data.
- Enter your estimate in the quickwrite as directed by your instructor.
- What is the value of looking at whole-class data?