Copper Recovery Lab Report

The percent recovery of the copper was calculated using the equation, percent recovery = (the mass of the copper recovered after all the chemical reactions/the initial mass of the copper) x 100. The amount of copper that was recovered was 0.32 grams and the initial mass of the copper was 0.46 grams. Using the equation, (0.32 grams/0.46 grams) x 100 equaled 69.56%. The amount of copper recovered was slightly over two-thirds of the initial amount.

Throughout the experiment, copper was altered a total of 5 times, but after the final chemical reaction, solid, elemental copper returned. Each time the solution changed color, a precipitate formed, or when gas appeared, indicated that a chemical reaction was occurring. For the first reaction, copper was added to nitric acid, forming the aqueous copper (II) nitrate (where the copper went), along with liquid water, and

There are only two circumstances in which I think the copper could have been lost. The first chance where some of the lost mass of copper may have gone could have been during the first reaction. If distilled water was added to the solution before the chemical reaction finished, some copper may have been lost during that step. While all nitrogen dioxide gas seemed to have dissipated, perhaps, it was not finished yet. By stopping the reaction early, all of the solid, elemental copper may have not had a chance to react with the nitric acid, and some mass may have been lost during the step. The other time where mass could have been lost was during reaction 3, more specifically each time the liquid was decanted. Although a few black sand-coffee grains of the copper (II) oxide lost do not seem like a significant amount, they do have an impact on the final result, and each time a few of the grains were accidentally decanted could have an impact on why our final recovered mass was less than the initial amount that we began