Identification of Copper (II) Chloride Introduction Through a series of cation and anion confirmation and elimination tests, the identity of an unknown compound can be determined. By subjecting certain standards to a series of tests, it will be known how they react when trying to identify the unknown. The results of these tests are crucial to correct identification of the unknown compound. Materials and Methods 0.5 grams of the unknown 11 was added to 5 mL of distilled water in a centrifuge tube to make the stock solution. To determine the cation, 6 M NaOH was added dropwise to the unknown solution until a precipitate was formed.
Repeat steps one and two 2. Place one drop of red dye into the test tube 3. Place one drop of yellow dye into the tube 4. Compare the controlled color to the new color 5. Clean up lab Data: Trial | # of Dye Drops | Color | 1 | 2 red, 1 yellow | Very dark red | 2 | 1 red, 1 yellow | Light colored red | Analysis: By first placing two drops of red dye, and one drop of yellow dye into the 10ml of water, the color became too dark of a red to match the controlled substance.
The M&Ms were selected from a larger bag of M&Ms with many colors. There were 5 M&Ms that were selected from the bottom of the bag and 5 that were selected from the top of the bag in order to increase the chance of a completely random sample. The M&Ms were then measured to the nearest one hundredth of a gram on an electric scale. We hypothesized that when the masses of ten M&Ms of the same color were collected, that they would not have the same mass. Since the amount of chocolate covering each peanut isn’t measured out there must be a difference in the mass of the M&Ms.
Reactions: Results: Calculations: Discussion: The TLC plate had 5 circles, indicating the 5 compounds, when it was under the UV lamp. Evidence shows that fraction 1 was the least polar because it traveled the farthest up the TLC plate. Fraction 2 was slight more polar than fraction 1, but less polar then fraction 3. Fraction 3 was the most polar because I traveled the least amount of distance. In all the separation was pretty successful in getting Rf values for the three fractions, and the two compounds.
This experiment was chosen to prove that different solvents and paper could be used to separate the different materials in black ink. The solvent being tested is water. This experiment’s main purpose is to be able to observe how chromatography can be used to separate mixtures of chemical substances. It was hypothesized that the paper with the water will be able to be used to separate the mixture into black ink’s five color components. The experiment should show all of the different substances in the black ink mixture.
Miller also found that people can recall 5 words as well as they can recall 5 letters- we chunk things together and can remember more. The capacity of LTM is not scientifically possible to measure. One key difference between the concepts of STM and LTM is duration. Duration refers to how long a memory lasts before it is no longer available. Peterson and Peterson conducted a landmark study of the duration of the STM.
Skip questions B, C, D, E and F in the lab manual, and answer these instead: A. What is the average % acetic acid in your vinegar sample? Standard vinegar is 5% acetic acid.How does your result compare with the standard? G. A 5.0 mL sample of vinegar was titrated with 7.2 mL of 0.55 M NaOH(aq). If the density of the vinegar solution is 1.00 g/mL, what is the mass percent of acetic acid present?
Less germinated in the presence of 1% ammonium nitrate compared to the spores not in the presence of ammonium nitrate. In other studies done, when ammonium is used to provide the nitrogen source for photosynthetic spores, they will not grow or germinate properly, and may show abnormalities and inhibited growth (Melan & Whittier, 1990). That is exactly what our experimental data showed us. After preforming the tests and compiling all the replicate data, we found that in the control group there was an average of 50.5 germinated spores per plate. In the plates containing 1% ammonium nitrate there was an average germination rate of 28.5 spores per plate.
Repeat steps 1-6 until three trials have been recorded. Results: Trial | Initial Volume | Final Volume | Total Volume | Color of the Solution | pH | 1 | .60mL | 8.6mL | 8mL | Bright Pink | N/A | 2 | 8.6mL | 14.9mL | 6.3mL | Semi-BrightPink | N/A | 3 | 14.9mL | 21.3mL | 6.3mL | Pale Pink | 7 Yellow | Analysis: The data that we collected, made us infer that the indicator, phenolphthalein, changes to a bright pink color in the presence of a basic solution. Our data also showed that the neutral solution had a lesser amount of NaOH than HCl. This would mean that the NaOH was more concentrated than the HCl. We then calculated the molarity of NaOH with the volume found in our data.
To this tube, we added 5mL-deionized water. After a while of swirling, we noticed that the reaction was over We then added 3 ml of water and mixed, recording any changes. After we noticed that there was no precipitate formed, we added another 5 ml of water, and stopped there because we observed a precipitate as expected. The content of the tube was separated form the zinc. The solution with the precipitate was divided in to two tubes and centrifuged.