Ms. Martin
IPS Per. 1
11-3-09
Sludge Lab Report
A few weeks ago, I got a container full of “sludge”. I was asked to separate it into its four components and identify each one to help me better understand how to separate mixtures ad identify substances. My original sludge had a liquid on top and solid(s) on the bottom. The liquid was clear, and most of the solid was tan. There was a small layer of blackish/brownish particles in the middle of the tan solid. There were small yellow “rocks” visible on the surface of the tan solid. For the first physical observation, I tried smelling the mixture. It smelled like permanent marker. Next I tried sticking a spoon in it and stirring the tan solid lightly. It looked like it was an …show more content…
extremely smooth sand. Finally, I tried drinking the liquid. Nah, I’m kidding! To start off, I will describe the liquid.
I separated it simply by using the decanting technique. I carefully poured it off of the mixture of solids and into a separate plastic cup. Easy. The physical property of phase was used for separation. It was the only liquid in the mixture. Then I had to identify it. I smelled it and it had a permanent marker smell to it. That led me to believe it was an alcohol. Next, I tried measuring the density using a graduated cylinder and a balance. I measured the amount of alcohol I put in the graduated cylinder (volume) and how many grams it was on the balance (mass). The volume was 9.2cm3, the mass was 7.25g, and the overall density was .79cm3. That proved my liquid was not water. Finally, I tested the boiling point to determine what type of alcohol it was. I used a ring stand, thermometer, hot plate, test tube, and a beaker full of water. I placed the beaker full of water on the hot plate. I then filled the test tube with my liquid and attached it to the ring stand. Finally, I put the thermometer in the test tube and turned the hot plate on high. The liquid really started boiling around 78 degrees (Celsius), so I concluded that my alcohol was ethyl …show more content…
alcohol. Next we have the blackish/brownish particle layer. To separate it, I used the magnetic retrieval technique. This tests the physical property of magnetism. I simply used a magnet to retrieve the particles and a toothbrush to remove them from the magnet into a separate paper cup. There’s only one substance that is magnetic, but I had to do two more tests. I simply checked solubility in water in alcohol. It wasn’t soluble in either. It was, obviously, iron filings. The third substance I decided to separate from the mixture was the tan sand.
After the liquid was removed, the solid wasn’t as silky and it was more like normal sand. I also discovered the “rocks” were actually clumps of this substance. ANOTHER thing I discovered was white/clear grains. Yes, it was a salt! That means there’s only one way to separate this stuff: dissolve and filter. I poured water onto the rest of the mixture and stirred it up for a solid minute or so. After that, I poured the water into a funnel lined with filter paper which dripped down into another cup. This left me with only the tan sand. First I tried smelling it. It had a REALLY strong smell. Secondly, I recalled it being in the alcohol with a few particles floating around. This got me to believe it was slightly soluble in alcohol. Finally, I tried testing solubility in water. It just floated at the top without any particles floating around in the water, so it wasn’t soluble in water. Due to these factors, I determined it was
sulfur. Last, but certainly not least, the white/clear grains. Before I evaporated the water, I took note that it’s soluble in water. To separate it from the water, I evaporated it off. I simply put it on a hot plate, set it on high, and poof. Only grains. By now I identified it as a salt. My next test was alcohol solubility. Turns out, it’s only slightly because the alcohol was very cloudy after the dissolving process. Lastly, I put a sample on a watch glass with some water and left it out over night to check crystal shape. In the end, the crystals were spear shaped, leading me to the conclusion that it was potassium nitrate. All in all, my sludge consisted of ethyl alcohol, iron filings, sulfur, and potassium nitrate. I think my only difficulty was that I discovered the salt fairly late in the process. Overall, I enjoyed this lab because I really felt like I was doing something a real scientist would do. Oh yeah, and I felt a feeling of loss once I had to throw my work away. Sniff.