Bleach Synthesis Lab Report

Aspirin Recrysalization Data Table Actual Mass (g) 0.41 Actual MP (ºC) 123-125 Expected Mass (g) 0.533 Expected MP (ºC) 135 Percent Recovery 77% Percent Error 8%

To prepare the penny samples three pennies were obtained with one penny assigned to each group member. Each penny was weighed and their masses were recorded in the notebook. The year the pennies were made and the condition the pennies were in were also recorded in the notebook. In the fume hood each penny was placed into a 150 mL beaker. 25 mL of 6 M HNO3 was added to each beaker. The pennies dissolved and the remaining solutions were left to cool for 10 minutes. The three beakers’ contents were quantitatively transferred into three separate 100 mL volumetric flasks using a funnel. To make sure there was no loss of sample, the beaker was rinsed with 5-10 mL of water four times, each time the rinse solution being added to the volumetric flask. Still in the fume hood, 14 mL of concentrated ammonia solution was added to each volumetric flask using a graduated cylinder. The volumetric flasks were swirled to establish the blue color and dissolve any solids. If any

The hypothesis is rejected as the density of the pennies did not remain constant. The results show a 8% failure rate. This failure could be due to the makeup of the pennies. “In 1982, the mint introduced a penny that is 97.6% zinc and only 2.4% copper with a density of 7.2 g/mL. By comparison, the old pre-1982 copper pennies were 95% copper and 5% zinc with a density of 8.8 g/mL” (Bularzik, 2007). This is a 22% difference in density between the pre-1982 pennies and pennies made after that year. A source of error could be that pennies from this experiment were made during different years and therefore had different metal percentages.

My PIRI experiment is ‘the effects of bleach on hair strength’ there are many factors that require research in order for me to have a better understanding for my experiment, as this experiment is not a very common one, I will research the main facets of this experiment individually to gain a more in depth knowledge of each aspect. Aspects that I need to research include hair (its structure and previous tests for strength conducted), bleach (what it is, how it works and how to dilute it correctly) and finally, force (how it works and how to measure it), these are the three main factors of my experiment.

An experiment that could test if the amount of vinegar results in different amounts of carbon

Objectives: The lab experiment will consist of oxidation-reduction and double displacement reactions as well as titration techniques. All these components will be used in order to determine the percent composition of pennies. In conducting redox and double displacement we are able to analyze a penny and figure out the chemical composition of the product. The experiment entails careful observations and recording of evidence for a chemical reaction. In this experiment

After performing the experiment, the results were that copper pennies have a greater density and mass than the zinc pennies. These results supported my hypothesis of since copper has a greater density than zinc, then the copper pennies will have a greater mass than the zinc pennies. Some errors that occurred during this experiment are the non-precise measurement of the water and how some of the copper pennies had grime on them because they were old. This extra grime caused the mass of the pennies greater. A precise measurement of 15 mL of water and clean copper pennies would improve the experiment and the amount of errors would be

This lab could have contained errors. The errors could have happened when performing the lab. Some of the possible errors in this lab are:

It was hypothesized that Cup 3 with the soda water would have the greatest amount of chemical weathering because of the soda water having the highest pH balance at the beginning of the experiment. Seeing that is was the most acidic; would create the most results. After conducting the experiment, the hypothesis was incorrect. After completing the experiment, the results for the soda water ended up being the cup with the second lowest change in mass of the rock. The rocks beginning weight began at 11.7g and ending at 11.6g., resulting in a change of -.01g. The rock that was in Cup 1 with the 50% vinegar solution had the greatest change in mass. The rock weighing at 8.3g, and then weathering down to 7.0g. Cup 1 had a total change of

This project explores the effectiveness of various cleaning solutions in cleaning tarnished and oxidized coins and the question that is trying to be solved is to find the best cleaning solution. If pennies are placed in lemon juice, apple juice, water, and baking soda paste the penny with the cup of baking soda paste will be the cleanest. My data is what was recorded during the experiment.

In the experiment, four nails rusted in water containing various concentrations of salt for fourteen days. At the end of the experiment, it can be concluded that nail three--the nail placed in the solution containing the highest concentration of salt--rusted the most, followed by nail one, nail zero, and nail two. At first, nail zero, which was placed in tap water, was rusting the quickest. However, it was the slowest to change color, which turned entirely gray by day twelve. The other nails, however, turned entirely grey by day two with black stains appearing on nail two. By day five, the amount of rust on nails one and zero rapidly increased while the formation of rust on nail zero slowed down. Nail two did not begin to rust until day five

In the three experiments that we did we extracted dan from strawberries, E.coli, and wheat germ. In each of the experiments we had to open the nuclear envelope in some way with the strawberries we did this by freezing them so that the expanding water would break the nuclear envelope and allow the dan to be extracted. We also smashed them up to help facilitate in the breaking up of the cells. In the wheat germ we used a mortar and pestle to grind the wheat into a fine powder to release the dna.

The purpose of this project was to discover how the pH level affects corrosion rate. The hypothesis was if the pH level affects the corrosion rate, then the lower the pH level is quicker the corrosion rate would be. This will happen because liquids below the pH level of 7 possess stronger acidic attributes. The effect of pH level on corrosion rate was determined by depositing a copper penny in each of three plastic cups, and then three different liquids by their pH levels, were assigned to be displaced into each cup formulating a chemical reaction to be observed. The results collected during this investigation contradicted with the intended result, this experiment was conducted to determine corrosion rate; Dana Puti Vingear (pH level: 4.5)

In this experiment, methyl benzoate was synthesized from benzoic acid and methanol with acid catalyze using Fisher Esterification. First benzoic acid and methanol were mixed in 100 mL round bottom flask. We cooled the mixture in ice and poured 3 mL of conc. H2SO4 and swirled to mix compounds. Then we refluxed the mixture for 1 hour. We let the solution cool and then decanted into a separatory funnel containing 50 mL of water and rinsed the round bottom flask with 35 mL of tert-butyl methyl ether and added that to a separatory funnel. We shook and vented thoroughly and drained the aqueous layer which contained a bulk of methanol and H2SO4. We washed the solution in the separatory funnel with 25 mL of water, followed by 25 mL of sat. sodium bicarbonate

The main purpose of this experiment was to synthesize a series of inorganic pigments, qualitatively observe their macroscopic and microscopic properties and perform a series of qualitative micro-chemical spot tests on them. The other purpose was to design a qualitative analysis experiment for the purpose of identifying an unknown inorganic pigment. In the first week of this experiment, barium white, zinc yellow and chromium oxide green were synthesized using macroscopic inorganic pigment reactions. The final yield of chromium oxide green was found to be 0.2001 g with a yield of 11.50 %. Prussian blue was synthesized using microscopic inorganic pigment reactions. In the second week of the experiment the micro-chemical