Curd Lab

In this lab, the purpose was to determine the stability of a substance after adding an acid or a base. The results claim that liver and buffer are the most resistance to change in pH. Looking at figure 3, buffer and liver both maintain a stable pH even with the addition of an acid or base. However, potato and water have less buffer in them since their pHs did change. In figure 3, the potato acid’s pH level decreased by two, and the potato base’s pH level increased by two. The level of pH of a water acid decreased by 4, while the water base’s pH increased by 5. These results all tie to the fact that buffer is a substance that maintains a stable pH; the presence of buffer in organisms help maintain homeostasis by binding or releasing hydrogen

In six different 50mL volumetric flasks there was 0.00 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00mL of the 5.00 g/L Cu^(2+)stock solution. 3mL of 15M ammonia was added into each flask, once the ammonia was added each flask was diluted with water to 50 mL then were all thoroughly mixed.

The purpose of this experiment was to find out the nutrient content of unidentified food samples and to use chemical reagents to see if the unidentified foods for sugar, starch, protein and fat (lipid) content. After comparing the color changes in each unknown substance then you will be able to see the amount of sugar, starch, protein or fat there is in the unknown substance.

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

After pouring the vinegar in the water the change was that the water seemed to be a shade darker when added it. The water appears to have clouded. Other than the smell a person would not be able to tell there has been something added to the water.

First students obtained 8 graduated cylinders and labeled them. Each one contained a different ratio of vinegar and water. These graduated cylinders with the liquid were weighed and recorded.Then, students obtained an Alka-Seltzer tablet and recorded its mass. Then one alka-seltzer tablet was dropped into each of the graduated cylinders. Students had to

Then added 5.00g of CuCl₂ ●H₂O into the distilled water. Stirred to dissolve the mixture

Place the beaker on the hot plate, place the thermometer in the beaker and set the hot plate to 5oC.

was to determine the percentage by mass of acetic acid in vinegar using acid/base titration. The

First, I measured out ¼ cup of white vinegar and poured it into the small plastic bowl. Next, I added 1 tsp. of salt into the vinegar and mixed until all the salt was completely dissolved. Selecting the dullest penny of all, I dipped it halfway into the liquid and kept it in the solution for about 20 seconds, and then removed it.

Throughout the course of the experiment, the weight of the beaker and liquid, the weight of the Alka-Seltzer tablet, the weight of the beaker with liquid plus the weight of the tablet, and the weight of the beaker with all of the contents after the bubbling ceased remained roughly constant and did not vary widely. However, a trend is able to be seen in Figure 1. It is clear that as the mL of vinegar used in each experiment run increased, the mass percent of NaHCO3 increased as well. During the construction of Figure 1, experiment runs four and six were deleted to create the expected graph which consists of a gradual increase and eventually leveling off into a plateau.

The density had to be determined by massing a known volume of the solution and dividing the mass by the volume. The percent by weight of acetic acid in the solution needed to be found by dividing the grams of solute from the grams of total solution. This required manipulation of the equations for density and molarity to reach the desired value. With this information, it was possible to compare both the molarities and the percent composition by weight of the vinegars to store bought

The results obtained matched what was expected when the experiment was started. The procedure was successful in the fact that the components of the milk were separated and the qualitative tests went

One milliliter of 6.00-M phosphoric acid was placed into a 125-mL Erlenmeyer flask using a volumetric pipette. Using a slightly larger pipette, six milliliters of 3.00-M sodium hydroxide was transferred into a 50-mL beaker. Then a disposable pipette was used to slowly mix the sodium hydroxide into the phosphoric acid while the solution was swirled around. Then both the beaker and flask were rinsed with 2-mL of deionized water and set aside. A clean and dry evaporating dish was weighed with watch glass on a scale. Then the solution was poured into the dish and the watch glass was placed on top. The solution was then heated with a Bunsen burner to allow for the water to boil off to reveal a dry white solid. After the dish cooled to room temperature it was once again weighed and the new mass was recorded.

Experiment to investigate the amount of sodium hydroxide needed to neutralize the solution of vinegar