Essay about Observations of Chemical Changes

Words: 1415
Pages: 6

Chem 181 DL1
Professor Snyder
Rebecca Hansen
Observations of Chemical Changes
9/10/12

Experiment: To examine the reactions of some common chemicals contained in
Consumer products and observe the macroscopic changes these chemicals undergo. Examining reactions of common chemicals contained in consumer products. In this lab, it will show the macroscopic changed the chemicals undergo.

Objective: To observe some properties of chemical reactions and to associate chemical properties with household products.

Chemicals used in this lab were: Ammonia (NH3) Bromthymol Blue (BTB), Copper (II) Sulfate(CuSO4), FDC Blue Dye #1, Hydrochloric acid (HCl), Lead (II) Nitrate(Pb(NO3)2), Phenolphtalein Solution- (C20H14O4 ), Potassium Iodide

The sample that was thought to be vinegar is not.
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?
a. I would interpret the result that the fifth cookie does not contain as much starch as the other four cookies. In my previous experiment, I had noticed that the starch actually turned slightly yellow-brown with a certain item used Therefore, I would assume that the first four cookies have starch whereas the fifth cookie clearly has far less than the rest, but still contains some
E. You decided to investigate if the new wave of VitaminWater is pH neutral: neither too acidic nor too basic. Using BTB (Bromthymol blue), you select five flavors of Vitamin Water to test. Three of the flavor-samples turn a murky green, indicating the likelihood of acid/base balance. Of the two remaining, one turns slightly yellow, while one remains blue. What can you assume about the acid/base content of these particular flavors of Vitamin Water?
a. When turn yellow and that if it is mixed with a base it will turn/remain blue. The Vitamin water that remained blue is a base. The Vitamin Water that turned yellow is heavier in its acids than its bases.
F. You have read that a new brand of hair tonic is supposed to contain lead (an ingredient in Grecian Formula). Devise a simple