50 % Vinegar Experiment

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

1. Develop hypotheses predicting the effect of pyrite and coal on the acidity of water?

Purpose: The purpose of this experiment is to observe chemical changes in common consumer products to determine if the chemicals are basic, acidic, or remain neutral when mixed with other chemicals.

The more acidic a substance is the less oxygen it will produce when going through a chemical reaction. During the Lab “How Do Changes in pH Levels Affect Enzymes Activity”, the researcher conducted an experiment to test the effects that an acidic, neutral, and a base substance will have when combine it with hydrogen peroxide. The data table shows that HCL (acidic substance) barley produced any oxygen at all when it was combining with Hydrogen Peroxide. The pH level for HCL was 2.5; this level indicates that the substance was very acidic. When the H2O and NaOH were tested they produced more bubbles than HCL. NaoH produced a little more bubbles than HCL. The pH that NaoH produced was a 9, which is a base. H2O produced more bubbles than both substances;

The limiting reactant of a chemical reaction is the substance that places an upper bound on the amount of product that the reaction can produce. The limiting reactant places this upper bound because the reaction must stop once all of the limiting reactant is consumed.

The purpose of the lab was to mimic the way Mendeleev placed the elements on the periodic table. Mendeleev was a Russian chemist who produced the first orderly periodic table. Frist, the way the periodic table has been classed alongside the atomic sum and the elements with related properties. Second, the objectives are observeing the physical states of common elements, and the progression of the periodic table, lastly speculate by determining the unknown elements established on the observed progression. As a group we tried to find out where the unknown elements should be placed. Finnly, the information that was given to help us with our process was the state, density, hardness, conductivity, melting point, and color.

Start the experiment by taking 3 agar cubes containing pH-indicator dye phenolphthalein, and have the teacher cut three different cubes each with different measures; a cube measured 3cmx3cmx3cm, another 2cmx2cmx2cm, and another 1cmx1cmx1cm. (The agar cubes are acting as artificial cells for this experiment). Place each agar cube in the solution of vinegar and water, and start the stopwatch as soon as the cubes hit the water. Stop the stopwatch as soon as the smallest cube becomes fully clear and record how much time it took for the physical property to completely change. The agar cube is supposed to change color from pink to white, the phenolphthalein dye gives the agar cube the pink color. The purpose of this experiment is to test the relationship

Scientist use rocks and

I suspected that the limestone in cup two would not lose as much mass as the limestone in cup one because of the lower concentration of vinegar. Additionally, the limestone in cup three, showed a decrease in mass less than the first two cups. It only lost 0.2 grams of mass. I did not anticipate the soda water would cause a great deal chemical weathering. Finally, the mass of the limestone in cup four decreased the least.

Other samples of the clay were taken to laboratories to be analyzed. Part of the results showed a large concentration of platinum and iridium. These elements are very rare on the surface of the earth at the moment but they are present in meteoric dust that rains down from space at a known rate. That rate allowed for a measurement of how long it took for the clay to form.

The hypothesis was if a more acidic solution is added then the limestone will dissolve more because stronger solutions break down the bonds between the particles faster. The data neither supports or refutes the hypothesis because although the acid did significantly break down the rocks, the molarity didn’t correlate directly to how much mass the rock lost. The rock that was dropped in only stayed the same weight before and after the experiment, 3.95 grams. The rock that lost the most weight was the rock that was in solution with a molarity of 2, in which the change in mass was about 2.71 grams. The rock that lost the second most amount of mass was the rock that was placed into the solution with a molarity of 1, where 2.49 grams was dissolved from the rock.

It was believed that if the amount of time that the rock went through heating and cooling increased, then the weight of the rock would decrease because while the rock goes through more heating and cooling eventually it will fracture causing the weight to decrease. This is called heat fracture. The data gathered did prove the hypothesis to be correct. For the longer trials with more minutes, the rock's weight did decrease more rather than the shorter amount of trials. For example, the one minute trial barely had a 0.6g difference proving our hypothesis correct, while the 15 minute trial had a significant change in the rock's weight due to the longer time experiment.

During this experiment, our concluding data almost perfectly validates Lavoisier’s law of conservation of mass, with only one oddball being the mass of the combined baking soda and vinegar after the chemical reaction. This oddball may be explained by a small spillage of baking soda that occurred just before the trial. Besides this one oddball, our data clearly states the both before and after the chemical reaction, the mass of the combined reactants remained the same. If we had more time to conduct this investigation, we might have added more than three trials, possibly with different amounts of each reactant to further analyze the reality of this law. We also would have attempted assessing this law by using the FAC’s room and finding the mass

There were three test tubes in which the experiment was held. A relatively equal sized portion of raw potato (this contained the enzyme [a biological catalyst] hydrogen peroxidase) was placed in each tube. Then, enough water to cover the potato was added. Proceeding this, each of the test tubes were assigned a temperature; cold, room temperature or warm (this was written on the tag so that they were not confused). The test tube destinated ‘cold’ was placed in a ice bath for five minutes. At the same time, the ‘hot’ test tube was placed in a hot water bath for five minutes. Meanwhile, the room temperature test tube sat at room temperature for five minutes. When the five minutes were over, the test tubes were returned to the rack (so that they were able to be observed). Then, the test tubes were allowed to sit at room temperature for five more minutes. Once that period of time was over, 2 ml of hydrogen peroxide (the substrate) was added to each tube.

It was hypothesised that the vinegar would cause the most decay as the vinegar is a strong acidic substance. As the pH level of the vinegar was low, it was very acidic resulting in a high mass loss of 95.784% as seen in Graph 3, Average shell mass loss percentage graph. The water that had a more neutral pH of 6 did not have a large decay like the vinegar. Its decay process was of a minor 0.014%. The soft drink had a somewhat acidic pH of 3.5 and a small decay percentage of 1.901%. The orange juice had a pH level of 4.5 but has the second largest decay percentage of 8.796%. The milk’s pH level was 6.5 and had a decay percentage of 0.560%. These results raised several reasons for decay in the range of liquids offered.