Electrochemistry Lab

6-3: This process is used by cells to manufacture _biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products__

It is a chemical reaction where the colors of both solution and iron strip changed. It is

The purpose of this lab was to make a substitutional alloy coating the penny in a gold color. The color of the penny depends on the Zinc and Sodium Hydroxide solution, and if heat was added or not. We took a copper penny and boiled it in a Zinc and Sodium Hydroxide solution. Then we took the penny out, rinsed it in water, and dried it off. Now the penny was silver. We then took the penny and waved it across a flame causing it to turn gold. Some errors that happened were getting Zinc in our water and over cooking the penny. These could be fixed by rinsing the Zinc off the penny in its solution before taking it out and not heating the penny for as long. A suggestion for improvement would be getting the flame at the lowest temperature possible.

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

Obtain a 50 mL beaker for the experiment. In the first part of the experiment, you dissolve the zinc core of a penny and leave the copper covering intact by putting four notches in

Day 1. Michael was coming home for vacation from college. When he got home he found out that

In this lab, we will determine the percent composition of a modern (post-1982) penny by using a strong acid to react and dissolve the zinc core, leaving only the copper coating. Once only copper remains, we will compare its mass to the entire mass of the penny to determine how much of a penny is copper and how much is zinc.

Then I attached the black clip to the coin and the red clip to the copper strip. I then placed each item in the copper sulfate solution and attached the opposite end of the black clip to the negative side and the red clip to the positive side of the battery. Then I waited ten minutes to observe the effects on the items. I then re-cleaned both items and followed the above steps, except the clips. I placed the red clip on the negative side and the black clip on the positive side of the battery. I performed this experiment with the coin and copper strip first and then re-performed the same experiment with the key and copper

I started with elemental copper metal and then reactions occur step by step as follows:

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.

Chemical reactions involving the transfer of electrons from one reactant to another are called oxidation-reduction reactions. In a redox reaction, two half-reactions occur; one reactant gives up electrons (undergoes oxidation) and another reactant gains electrons (undergoes reduction). In the case for galvanic cells, redox reactions occur spontaneously. A measure of the tendency for a reduction to occur is its reduction potential (E), measured in units of volts. At standard conditions, 298 K and concentrations of 1.0 M, the measured voltage of the reduction half- reaction is defined as the standard reduction potential (E°).

When I was at my neighbor’s house their TV remote batteries died. This prompted them to go to their fridge and get new batteries. When I saw the batteries in the fridge, I asked myself, “What effect do temperatures have on batteries?”. Ever since then I have wanted to know what affect extreme temperatures have on batteries. If extreme temperatures do affect batteries will batteries be able to withstand these extreme conditions? These questions prompted me to perform this experiment on batteries.

The zinc begins to have a positive charge of two after two electrons are removed from each zinc atom (“Digging Deeper”). The zinc ions stay inside of the lemon and the area around where the screw was placed inside of the lemon begins to darken (“Digging Deeper”). The second reaction that occurs is called Reduction. Reduction is the gain of electrons during a reaction (Helmenstine, Ph.D. Anne Marie. "What Is the Difference Between Oxidation and Reduction?").

At the opposite end of the lemon, using the paring knife make a small slit in the lemon peel. Insert the penny into this slit and continue to push until only about a quarter of the penny remains above the peel.

And copper (II) ions were reduced to copper because it gained electrons and its oxidation number changed from +2 in copper (II) ions to 0 in copper.