Original Lab - Chemistry

. Questions:

A. Suppose a household product label says it contains sodium hydrogen carbonate (sodium bicarbonate). How would you test this material for the presence of sodium bicarbonate?

To test the material I would heat it up over a flame if it were a powder, as sodium bicarbonate turns a bluish color when exposed to flames.

B. You know what color phenolphthalein and bromothymol blue turn when testing an acid or a base. Use the empty pipet in the Auxiliary Supplies Bag to test several (at least 3) household items including household cleaning products with bromothymol blue. Rinse the pipet well before using it on the next household chemical. When finished with this experiment rinse the pipet well and return it to the Auxiliary Bag for use in future experiments. Name the items tested and record their results. What do these results mean?

Bleach: Phenolphthalein turns pink meaning that bleach is a base.

Windex: Phenolphthalein turns pink meaning that windex is a base.

Sprite: Phenolphthalein turns clear meaning sprite is an acid.

C. You found a sample of a solution that has a faint odor resembling vinegar. You are verifying that it is indeed vinegar and you add a few drops of phenolphthalein. The sample turns pink. What assumption can you make about this sample?

It would be safe to assume the solution is basic since the phenolphthalein turned pink, which means that you can no longer assume the solution is vinegar as vinegar is acidic and would have made the phenolphthalein turn clear.

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D. While performing a starch test on several different cookie brands, four tests result in the typical black color of starch-presence, but the fifth gives a yellow-brown color. How might you interpret this result?

I would interpret the result that the fifth cookie does not contain as much starch as the other four cookies. I would assume that the first four cookies have a lot of starch whereas the fifth cookie contains smaller amounts of starch.

E. You decided to investigate if the new wave of Vitamin Water is pH neutral: neither too acidic nor too basic. Using BTB (bromothymol blue), you select five flavors of Vitamin Water to test. Three of