Chem Lab Project 2 Essay

In reference to the analysis of anions, Table 1 shows that a precipitate was formed when our unknown was combined with HNO3 and AgNO3, thus indicating the presence of a chloride ion. Because our unknown did not form a precipitate due to HCl and BaCl2, separate, effervesce, or smell, we concluded that neither sulfate, nitrate, carbonate nor

Prepare the unknown anion solutions for the students to analyze from the four 0.2 M stock solutions of anions. Any combination of these four anions may be prepared. Using a graduated Beral-type pipet, add 2 mL of each ion selected to a 13 X 100 mm test tube. Add distilled water to give a total volume of 8 mL. Stopper the test tube. A matrix of combinations, similar to the cation unknowns, can be generated for the anions.

In this experiment, a saturated calcium sulfate was already made and ready to use. 25.00 mL of this solution was then mixed with 10 mL of an ammonia buffer and 1 drop of

In part, B the liquid that was decanted in step 3 was to be tested for the presence of either the presence of Barium or Calcium. The solution was mixed with Ammonium hydroxide and then it was tested to make sure the solution was basic. Ammonium carbonate was then added and the solution was heated, cooled, centrifuged, and the liquid was discarded. The precipitated was washed with water and centrifuged.

In this lab an unknown metal cation is identified by comparing chemical reactions of known metal cations with different ions to chemical reactions of the unknown with those ions.Nine different metal cations are reacted with sulfate, iodide, carbonate, hydroxide, and ammoniaand observed. A procedure is then planned using the original tests to identify the unknown metalcation.

We used a Bunsen burner, Ni-Cr wire, and the eight different metal ions for this lab. We had to place several drops from one of the solutions on the end of the Ni-Cr wire, then one person holds the wire in the flame, and the others observe the colors of each solution through the spectroscope, then record data, and then repeat each step for the other solutions. When done, clean the wire and any spills and turn off the Bunsen burner. For the unknown substance (number 3), we found out that it was barium because when we did the flame test on barium, it’s flame color was yellow and it was yellow for the unknown too. Also, the unknown and barium had the same colors on the spectroscope reading and the three colors were close to being on the same number, and the unknown didn’t fit with any of the other solutions’

Overall this experiment was successful, as it was possible to determine which unknown salt solution the cation belonged too, and also the pairing anion. To figure out the cations, many tests and observations were needed to be made. With the gathered flame test results, and the information given in the procedure, conclusions could be made. Solution A is Sr2+ since it tested crimson red. Solution C is Ba2+ because it tested green. Solution D is Li+ because it turned the flame carmine red. Finally, solution G is Na+ because the flame had an intense colour of orange-yellow. The other ions did not give any specific flame test colour. The next test used was the litmus test, and it determined not only a cation, but also two anions. The acidity, and the basicity of each solution were tested in the litmus test. When the solution is dropped on the paper and it turned the litmus paper red, it means that the solution in acidic. In this case solution E turned the litmus paper red, proving that H3O+ cations are present. Solution D and G turned the litmus paper blue which means they are both basic solutions, and either OH- or CO32- anions are present. Left unknown still are solutions B and F, however; solution B can be concluded to be Co2+ by qualitative observations. Solution B was clear and light red/pink, and by conducting research it was determined that Co2+ solution contained the same colour, (Brunning, October 3, 2015). Finally Ag+ was determined to be the cation of unknown

The purpose of the experiment was to react cations with various substances labeled in the lab handout and create a flow chart that will allow me to identify unknown cations. Through my results I was able to develop a flow chart, which can help me to identify the cations I tested.

Part A: In the potassium iodide solution, I think there were potassium atoms as well as iodine atoms. In the lead nitrate solution, I think there were lead and nitrate ions. The potassium atoms and the lead atoms can be classified as cations, since they are metals. The iodine atoms and the nitrate ion can be

In conclusion we ended up solving the mysteries of the mystery elements. The results were that mystery element A was Ammonium Hydroxide, B was Mercury(II) Chloride, C was Potassium Chromate, D was Silver Nitrate, E was Iron (III) Chloride, and F was Mercury(II) Nitrate. Possible errors in the lab could have been chemical mixtures, data collection, cleanliness of hands and clear chart, and possible data crossing. Our hypothesis was mostly correct but some parts were incorrect. The parts of a hypothesis that were incorrect or the predictions of all the clear liquids. What I had learned from this lab is how to predict and find out what chemicals are based upon data and testing. This could be used in other parts of science because you are using your data to predict other things. I would enjoy trying this experiment again with more mystery chemicals to try and

This requires many different tests to determine what substance each one is. Things like over the counter drugs such as used in part 1 can be easily accessed. Some require that a person only has a certain amount of them. They are typically used for medical uses; aspirin can be used as pain relief and to help for fevers. When given an unknown, it is possible that these drugs can be compared by how they react with other substances. Test 1 revealed that it was simple with careful observation to determine what an unknown is and to therefore use those results across multiple

Repeated the steps 1-3 with all the solutions that still need to go through the experiment.

The Biology Department requested the identity of seven different samples. The aqueous ionic solutions were sent to be disposed of by the company Enviro Safe, Inc. However, the shipment containing seven, five-gallon carboys, was labeled Experiment 9 and did not include the names of solutions. The faculty in the Biology Department was unfamiliar with the contents but was able to locate a pre-laboratory notebook dated ten years prior, the notes only revealed that eight unknown solutions were involved in the experiment. Enviro Safe would have charged $350 per carboy to analysis the products if not identified by the laboratory class. In order to save the department money all seven samples had to be labeled correctly and the identity of the one missing solution revealed. To fulfill the Biology Department’s request, the experiment involved mixing the solutions together two at a time so the reactions, if any, could help determine the names of each solution.

1. 10 drops of 1 M K2CrO4 was added to the solution and stirred for about 10 minutes.

To one test tube, 1 mL of 0.1 M NaI was added, to the second test tube 1 mL of 0.1 M NaBr was added and to the last test tube, 1 mL of 0.1 M NaCl. To all three test tubes, I added a few drops of AgNO3, stirred with the glass rod and proceeded to centrifuged each sample for approximately 1 minute. After each solution was centrifuge, the precipitate was formed. The solution was then discarded, and subsequently added enough 6 M NH3 to promote dilution of the precipitate formed prior. Only the precipitate which