Mystery Powders Lab Report

Our objective for the Sherlock Holmes Experiment was to illustrate that some chemicals can be identified or differentiated by simple chemical tests, such as solubility, pH, or color tests. In our group we had to test come common powders such as Alka-Seltzer, baking soda, flour, Vitamin C (ascorbic acid), and salt. Other chemicals that were used to do this experiment were vinegar, and Iodine 2 Solution. The equipment used to do this experiment was red litmus paper, and 5 test tubes per group.

mL cylinder to the beaker on the stir plate and empty it into the beaker. Place the pH probe in the beaker and record the pH in the data table. Drag the beaker to the red disposal bucket. Double-click the bottle of NaHCO3 to move it to the Stockroom counter. Repeat steps 5 and 6 for KNO3.

Immediately we count off baking soda, salt, and sugar because in the first test with the microscope, they show all crystal arrangements unlike the powder in our mystery. Then we go on to count off the plaster of Paris because in the vinegar test, it does the opposite of our mystery powder, it mixed with the vinegar while our powder sat on top and started to harden. At this point we are down to flour and corn starch these two show the same results in the iodine test the both turn into a thick black gel. Continuing on to the heat test they show generally the same, but the flour starts to smoke unlike the corn starch just turning brown after a while, but this is still a pretty close difference between the two so then we go back to the vinegar test where the corn starch sat on top and hardened the flour just sat on top of the vinegar so now this is two differences we have found comparing the flour to our mystery powder. In the end the one that had all the same results as the mystery powder was the corn starch this proves our hypothesis to be correct but there should be more to our hypothesis because the crystals found in the substance therefore it must have one of the crystal substances in it also such as baking soda, salt, sugar or plaster of

* With a glass rod lift a drop of the starch solution from the test

Refer to the Lab Manual for Part A and B and the Cleanup pages 2-3 and 5.

7. Clean test tubes with test tube cleaner and warm soapy water in the sink.

The vinegar test would be just looking to see if theirs carbon dioxide. The iodine test would be seeing if there's any starch. And finally for the heat test we would be looking for noise, if the powder was on fire, smell, and the shape it made if burnt onto the foil spoon like if just went around the edges. It is important to support your hypothesis by going to check all your data you wrote down because your hypothesis might be right. And you can also go back and retest some powders just in case to see if you actually got the right information. Some precautions I took to avoid contamination was to not let the iodine get on my fingers or my hands. And to try not to touch any of the powders that got tested on. Like for example iodine was in powder “A” and I was the one mixing it I would probably not try to get it on my fingers because iodine is a poisonous substance. To improve this lab, I would probably do nothing because my group and I got the lab to sun smoothly. We got the lab to run smoothly by following directions and not fooling around with the foot powders and the

Experiment 1: First, fill the Graduated cylinder to 100 ml and pour it into the cup. Then add 58 ml to the cup. Guess the amount of paper clips you think will fit and then add the paperclips and record your information. Example 2: first, fill the cup with 1 ml of soap, then add 100 ml of water, and then stir it. Then add 48 ml. of water and guess the number of paperclips and then do the experiment and record your data.

3. In one of the test tubes add sugar and mix it in with the water

Return the petri dish to the teacher for disposal and begin working on the formal lab write

Then that morning we worked on trying to replicate the Mystery Mixture and trying to replicate that. Then as that class went on then a few more people got confident with their mixtures that they had. Then than we also had a dissection that day to find out what all of the class think that they can do net to find out then they said what about putting water or some other substance to it. Then Mrs.Riorsion said I’ve got some water that the class can use so that is what we can use to see what that can

4.Measure 35mL of warm water and add them into each of the 4 test tubes at about roughly the same time. It is essential that the water is warm. Do not seal the test tube.

Clean the graduated cylinder and graduated pipet with distilled water for use in the next dilution. (Vorndam, 2002, p. 97)

In order to perform this experiment, proficiency with using spectrometers, burettes, volumetric flasks, weighing by difference, and making a hot-water bath are essential1.

This labaratory report shows that when presented with an unknown chemical substance, identification of that substance is revealed through a seires of tests that involve chemical and physical properties of that substance.