Determining the molarity of a potato

Describe the relationship between the change in mass and the molarity of the sucrose in the dialysis tube. Based on scientific principles, did you observe what you expected?

Determining the molarity of a potato

Describe the relationship between the change in mass and the molarity of the sucrose in the dialysis tube. Based on scientific principles, did you observe what you expected? If not, suggest a reason or possible errors in set-up or data gathering. Why did you calculate the percent change in mass rather than simply using the change in mass?

Predict what would happen to the mass of each bag in this experiment if all the bags were placed in 0.

A dialysis bag is filled with distilled water and then placed in a sucrose solution.

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Calculate the percent change of mass, showing your calculations. If water moves out of the cell, the cell will shrink.

If water moves into the cell, the cell may swell or even burst. In plant cells, the presence of a cell wall prevents the cells from bursting, but pressure does eventually build up inside the cell and affects the process of osmosis. When the pressure inside the cell becomes large enough, no additional water will accumulate in the cell even.

So movement of water through the plant tissue cannot be predicted simply through knowing the relative solute concentrations on either side of the plant cell wall.

Instead, the concept of water potential is used to predict the direction in which water will diffuse through living plant tissues. In a general sense, the water potential is the tendency of water to diffuse from one area to another.

Water potential is expressed in in bars, a metric unit of pressure equal to about 1 atmosphere and measured with a barometer. Consider a potato cell is placed in pure water. Initially the water potential outside the cell is 0 and is higher than the water potential inside the cell.

Under these conditions there will be a net movement of water into the cell. The pressure potential inside the cell will increase until the cell reaches a state of equilibrium. Pour mL of your assigned solution it will be one of the six solutions listed above in Exercise 2 into a beaker.

Slice a potato into 4 equal cylinders or slices, they will resemble french fries. Determine the mass of all 4 potato cylinders together and record. Place the cylinders into the beaker with your assigned solution and cover with plastic wrap.AP Biology Lab: Osmosis and Potatoes the isotonic point of a sucrose solution and a potato 2.

50mL of solution for each molarity, cut and weigh potato. Allan J. Cessna, in The Triazine Herbicides, Use of UV/Ferric Ion and UV/Ferric Ion/H 2 O 2.

The use of ferric ions to sensitize the photolysis of triazine herbicides in water has been investigated as a means to detoxify pesticides. Determining the Osmolarity of a Potato Mishal Hasan Abstract Students in Biology find it difficult to understand the concept of tonicity and osmolarity in a real time situation.

Chemistry comes into play in the form of chemical probes or as compounds being evaluated as potential leads or drugs. The use of chemical probes to elucidate biology is the basis of chemical genomics. According to Clemson University, the molarity of a white potato is estimated between and when it is submerged in a sorbitol solution.

Determining the molarity of a potato

Molarity stands for the number of moles of a solute required to dissolve in one liter of a solution. The type of solution used will affect the molarity of the substance.

EXERCISE 1C: Determining the Water Potential of Potato Cells Introduction: Water potential was defined above as an expression of the tendency of water to diffuse from one region to another. Water potential is a numerical value that must be determined for a given temperature and pressure.

AP Biology Lab: Osmosis and Potatoes by sandra yuwono on Prezi