Report Submitted: June 17, 2012
Title of Experiment: Observation of Chemical Changes
Purpose: To examine the reaction of common chemicals from household consumer products, and the changes they undergo.
Procedure: After combining the chemicals listed below in Data Table 1, I observed the mixture against white and dark backgrounds by slipping white and black paper underneath the well plate. For every reaction, I wrote down the chemical combination, the well number, and my observations of the chemical reactions against the white and dark backgrounds.
Observations: Data Table 1: Reactions Expected | Well #/ Question | Chemicals | Reaction | A | NaHCO3 and HCI - C02 | The mixture didn’t look any different amongst the contrast of each colored background. | B | HCI and BTB | The mixture is orange. The color doesn’t change amongst the contrast of each colored background. | C | NH3 and BTB | The mixture is blue. I expected the mixture to turn orange | D | HCI and blue dye | The mixture is green. | E | Blue dye and NaOCI | Prior to adding the HCl the mixture was light blue, after the addition of HCl the mixture turns yellow. | F | NaOCI and KI | Prior to adding the starch the mixture turns brown, after adding the starch the mixture turns black. Foods tested: American Cheese- No starch, Fig Newton- Starch, Goldfish Cracker-Starch. | G | KI and Pb(NO3)2 | Mixture turns yellow & the precipitate after an hour lapse in time turned solid. | H | NaOH and phenolphthalein | Mixture turns purple. | A-2 | HCI and phenolphthalein | The mixture looked as if it remained clear on the white background, but when placed on the black background the mixture appeared cloudy. I expected when mixed w/an acid it would turn yellow and w/ a base it would turn blue. | B-2 | NaOH and AgNO3 | The mixture turned a cloudy brown color. | Paper Towel | AgNO3 and NH3 | After exposing the mixture to a 60 watt