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Diffusion Lab

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Submitted By janga01
Words 535
Pages 3
Fatmata Diffusion
Abstract dialysis tubing is, made of cellulose because it’s a selectively permeable membrane. In this experiment, we are testing to see if the solution in the beaker moves into the dialysis bag. Which because of that,
Introduction
Diffusion and osmosis are two types of transport mechanisms. Diffusion is the movement of molecules from areas of higher concentrations to areas of lower concentration until the molecules are evenly distributed through the area. Osmosis is the dispersion of water. Our cells are capable of absorbing nutrients because, the cell membrane is selectively permeable (some molecules can diffuse freely through the membrane while others cannot). In this experiment we used dialysis bag as a model of the cell membrane. Our hypothesis was that the glucose will diffuse out of the membrane into the beaker filled with iodine solution.
To demonstrate dialysis tubing we used water, starch and iodine. When starch and iodine react together they form a dark brown color.
Materials
Rubber band | Dialysis bag | Beaker | Glucose solution | Iodine solution | Water, thread |

Methods * Cut a piece of dialysis tubing that has been soaking in water approximately 40 cm (approx. 16 in) long, Tie the end of the dialysis tubing with two or more knots. * Fill the bag halfway with glucose solution. And add 4 full droppers of starch solution to the bag. * Hold the open end close while you mix the content o the bag. Rinse of outside the bag with tap water * Fill the beaker 2/3 full with distilled water. Add drops of iodine solution until an amber (tea like) color is apparent. * Place bag in the beaker with the open end hanging over the edge. Secure the open end of the bag to the beaker with a rubber band. Don’t let the content spill into beaker. Allow the setup to sit for 30 minutes * Record the color of the solution...

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