Reference no: EM133418229

Experimental procedure:

Cut a potato tuber into small 4 x 4 x 4mm cubes. Place 50 of these into a test tube and fill with .05% solution of methylene blue. In another tube place 50 boiled potato cubes and fill with .05% methylene blue. Label each tube with a grease pencil and stopper tightly so that no air is trapped in the tubes. Set them aside until the end of the period when you will examine them for any color change (see fig.2 ). Set up a second set of test tubes, this time fill both tubes with raw potato cubes and methylene blue. Label each tube with a grease pencil and stopper tightly so that no air is trapped in the tubes (Figure 3). Set them aside until the end of the period, when you begin your observation of the first set of test tubes (Raw and Boiled) remove the stopper of one of the tubes (Raw or Raw). After a 5 minutes observe the two tubes and note any color change of the solution near the top of the ustoppered tube.

After two hours the stopper was removed from the tube on the right. After a few minutes a change in solution color at the top of the tube begin to appear. Give an explanation for the color change. Hint: You will have to use your thinking skills to answer the following question--to set you on the correct path, consider what happens to your favorite soda when you remove the cap and why you replace the cap once it has been opened if you decide not to drink the entire soda.