Development of an Equation Essay
Purpose: Investigate a chemical reaction using lab procedures and observations. Then, find a pattern of reactivity and explain the findings using a chemical equation and particle diagram.
Procedure: Refer to: Department of Chemistry, The Ohio State University. "Development of an Equation." General Chemistry 1210 Laboratory Manual. Vol. 2013-2014. Plymouth: Hayden-McNeil. 32-35.
Part A: In the potassium iodide solution, I think there were potassium atoms as well as iodine atoms. In the lead nitrate solution, I think there were lead and nitrate ions. The potassium atoms and the lead atoms can be classified as cations, since they are metals. The iodine atoms and the nitrate ion can be …show more content…
Inferences: What anions are in the precipitate? -iodine (I-) When compared with results from part B to test anions, similar results were found. A dark red precipitate was formed in both.
(Testing for cations)
Reaction with hydrogen sulfide observations- A small, violet-black precipitate formed at the bottom of the test tube and the liquid solution was grey and cloudy.
Inferences: What cations are in the precipitate? – lead (Pb2+) When compared with results from part B to test cations, similar results were found, A violet-black precipitate was formed in both tests.
Exchange reaction- Positive potassium started off with negative iodine, and positive lead started off with negative nitrate. Potassium switched to combine with nitrate and lead switched to combine with iodine.
Part D: Testing of Precipitate | Observations on Initial Precipitate Formed (relative amount, etc.) | Lead Nitrate: Potassium Iodide Ratio | Tube 1 | Powdery, yellow precipitate formed at the bottom. Not very much precipitate. Little to no streaking. Clear liquid solution above precipitate. | 3:1 | Tube 2 | Powdery, yellow precipitate formed at the bottom. Equal to tube 1. Little to no streaking. Clear liquid solution above precipitate. | 2:1 | Tube 3 | Powdery,