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Osmosis & Osmotic Concentration

Question:  What is the osmotic concnetration of potato tissue?


Prepare Solutions
  1. Make 2 liter of stock solution of 1M sucrose (C12H22O11) solution (342 g/mole).  Use the Molecular weight calculator.
  2. Using this stock solution, make 200ml with the following concentrations: 0.8M, 0.6M,0.4M, and 0.2M.
Collect and Analyze your data
  1. 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
  2. Enter the mass of each cube in the data sheet
  3. Place one potato cube in each of the following solutions:  1.0M, 0.8M, 0.6M,0.4M, 0.2M, and 0.0M sucrose
  4. Determine the mass of each cube near the end of the period. and enter the value  in the data sheet.
  5. Graph the percent change in mass as a function of time. 
  6. Estimate the osmotic concentration of the potato tissue. 
  7. Enter your estimate in the quickwrite as directed by your instructor. 
Analyze the class data 
  1. Examine a plot of the class data of percent change in mass as a function of time.
  2. Estimate the osmotic concentration of potato tissue from whole class data.
  3. Enter your estimate in the quickwrite as directed by your instructor. 
  4. What is the value of looking at whole-class data?

Question: What is the osmotic concentration of celery tissue?

  • Devise your own plan of estimating the osmotic concentration of celery

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