Lab 3a

This labs objective was to determine how much copper is in a penny. Concepts that were used for this lab were calibration curves, and oxidatoin of metal.

The purpose of this lab was to determine the empirical formula of copper oxide compound. In the lab, hydrochloric acid and copper oxide compound was mixed until it formed a blue solution. An oxidation-reduction reaction, a reaction in which there is an exchange of electrons between elements, was performed by adding zinc to the solution to displace the copper in copper chloride. Zinc, in this case, was oxidized by losing two electrons (0 → 2+) while copper was reduced by gaining two electrons (2+ → 0). Also, when the copper was displaced, it became a precipitate, which is a substance that comes out of a solution as a solid due to insolubility.

The purpose of the experiment is to cycle solid copper through a series of five reactions. At different stages of the cycle, copper was present in different forms. First reaction involves reaction between the copper and nitric acid, and copper changed from elemental state to an aqueous. The second reaction converted the aqueous Cu2+ into the solid copper (2) hydroxide. In the third reaction Cu(OH)2 decomposed into copper 2 oxide and water when heated. When solid CuO reacted with sulfuric acid, the copper returned to solution as an ion (Cu2+). The cycle of reactions was completed with the reaction where elemental copper was regenerated by Zn and Cu

Washing of the copper is necessary in this experiment to separate the iron from the copper and make sure the iron is not counted in the mass of the copper.

The Cu Later lab experiment is designed to allow you to practice lab skills in implementing and performing a series of reactions. Specifically, four types of chemical reactions will occur: oxidation/reduction; double replacement; single replacement; and decomposition. You will begin with a known amount of copper metal, which, after progressing through several steps, is reproduced. In this experiment you will observe and record the various changes such as heat, color changes, and production that occur. This procedure is used to observe some chemical reactions of copper and its compounds while also performing the lab appropriately as to retain the copper as much as

3. Examine the luster of the minerals in Figure 1.2 (p. 4 lab book). Place the letter A, B, C, D, or E in

“What happens when you put acid on different minerals?” (Formoso, Acid Test: How to tell Minerals Apart , 2013)

The white color implies that chlorine is within the mineral oil, thus did not react. Since chlorine did not react, it means that bromide isn’t a possible anion, leaving chlorine as the anion. In procedure 5, the unknown compound produced water on the watch glass indicating it could be a hydrate. The hydrate test was inconclusive because the number of waters of hydration shown in Table 5 was half way between being lithium chloride monohydrate and lithium chloride 2. The percent error, shown in Table 5, between the expected percent of water in lithium monohydrate and the accepted value, was high at 40% which meant that the unknown could not be properly identified as a hydrate. Repeating the hydrate test produced a similar percent which is shown in Table 7. The reason for these high percent errors is because lithium chloride and lithium monohydrate are both hygroscopic. In addition, Table 6 shows an increase in mass when unknown #42 was left outside, which suggest that the unknown compound is

12) Find and extract the remaining copper wire out of the mixture using forceps and rinse the copper wire with distilled water so that the water goes into the plastic container.

Before the synthesis of the Copper Iodine Compound, the identities provided (CuNO3)2 and Nal weighed 1.65 g and 4.7 g, respectively. After being weighed, the (CuNO3)2 exhibited a blue color, while the Nal, through observation, was a white color. However, when both identities were combined, the product turned into a brown and red rocky material. Once 20 mL of deionized water was added, the product quickly turned pale pink paste. After the solution was repeatedly washed with a total of an additional 100 mL of deionized water, the product was powdery and pink with small grains, and was left to air-dry. Once the product was air dried, it was observed to be a pale pink color, while the filter paper was stiff as the product was hard and dry. Therefore, the solid was scraped off onto a recrystallizing dish. However, the mass of an empty recrystallizing dish needed to be recorded in order to compare how much of the synthesized copper iodide was obtained. Within this case, the empty recrystallizing dish used weighed 32.01 g, the product on the empty dish weighed 1.03 g, having a total weight of 33.04 g.

XIV. Record your observations of the dried, cooled copper metal and weigh the recovered copper.

Refer to the reaction of iron nails with a copper solution assignment in Module 3, Section assignment 3.4 Part F of the Chemistry 11 course.

Purpose: The purpose of this experiment was to observe the many physical and chemical properties of copper as it undergoes a series of chemical reactions. Throughout this process, one would also need to acknowledge that even though the law of conservation of matter/mass suggests that one should expect to recover the same amount of copper as one started with, inevitable sources of error alter the results and produce different outcomes. The possible sources of error that led to a gain or loss in copper are demonstrated in the calculation of percent yield (percent yield= (actual yield/theoretical yield) x 100.

The lab performed required the use of quantitative and analytical analysis along with limiting reagent analysis. The reaction of Copper (II) Sulfate, CuSO4, mass of 7.0015g with 2.0095g Fe or iron powder produced a solid precipitate of copper while the solution remained the blue color. Through this the appropriate reaction had to be determined out of the two possibilities. Through the use of a vacuum filtration system the mass of Cu was found to be 2.1726g which meant that through limiting reagent analysis Fe was determined to be the limiting reagent and the chemical reaction was determined to be as following:-

Everything in this world is made from some sort of natural resource. Even the pants you are wearing now, whether they are jeans or khakis. Although these things seem great and helpful, they can have serious impacts on society if not properly taken care of. One such object that can have a large impact on society is copper. You will be exploring the concepts of synthetic materials, natural materials, impact on society, taking a closer look on the process of refining copper and how it can used, and what effects refining copper can have on society.