Forensics C

[haverstall]

While I don't test powders, I would say my partner gets 8 powders done in about 10-15 minutes. At Regionals and State, we've been able to at least double-check all the powders. In the same time, I did fingerprints, mass spectroscopy, and I think polymers? We didn't have to do a write-up though, so were weren't as cramped for time.

I should clarify: when I say 20 minutes for 8 powders, I mean to be sure (or as sure as I can get). That often includes multiple tests to double-check a particular powder, so that's built in to my time estimate. And wow, no write-up... lucky I've never had an event without significant analysis at the end.

I was pretty sad about no write-up, but it does help keep your mind concentrated on just finding what is what. It also works in my favor, since I don't ever think I've actually succeeded in writing a quality write-up.
That being said, I do enjoy writing it; I'm just not that great at it.

[Steelfoam]

Does anyone have the order of beetles, not in my forensics book!

[Flavorflav]

Does anyone have the order of beetles, not in my forensics book!

Beetles are Coleoptera.

[Dragonshark]

Amazingly, we managed to win Forensics at state. The exam was pretty hectic and the supervisor wasn't exactly the nicest person in the world. We were worried that we would be disqualified because I formatted my notes such that I could rip out my flowchart for qualitative analysis while my partner had the notes for the other things, but that was apparently not allowed. Both of us didn't really know how to adjust the bunsen burners which were not like the ones we normally use, and the room smelled completely of gas, effectively masking the smells from burning fibers. There were things on the exam that I swear weren't on this year's rules, such as gas chromatography and arson. However, the chromatography was only matching pictures, which was much easier than developing a paper chromatogram. The question about arson asked why the victim's body didn't completely burn up from the fire. We didn't really know the answer to that question, so we just put down "oxygen deprivation." There was also an exhibit in the front of the room where we had 3 minutes to examine. It was an empty water bottle with some fingerprints on it, though it was pretty straightforward.

The supervisor also seemed to really want concise answers. We were allowed to write 5-10 words total for each section and were only given half a page to write the essay.

[bloods]

NY forensics test required knowledge of Sherlock Holmes. I feel so stupid for never reading that...

[Phenylethylamine]

NY forensics test required knowledge of Sherlock Holmes. I feel so stupid for never reading that...

Really? I did the NY Forensics test (got fifth, actually), and I somehow completely missed any reference to Sherlock Holmes... I mean, I guess I was holed up with the powders for two-thirds of the time, but still.

I was hoping for some cornstarch (because Oobleck) or ammonium chloride (because it makes such a pretty blue with Benedict's), but ah well. The potassium chloride was nice, that's always a pretty flame test.

[Steelfoam]

Does anyone have a good way to tell the difference between MgSO4 and Ca(NO3)2 besides the flame test. Does anyone from the wisconsin C -div state want to compare what they got on the powders?

[Dragonshark]

Does anyone have a good way to tell the difference between MgSO4 and Ca(NO3)2 besides the flame test. Does anyone from the wisconsin C -div state want to compare what they got on the powders?

I think there's a pH difference (MgSO4 is slightly acidic, while Ca(NO3)2 is neutral), but honestly, I'm not sure on this one, since I only use the flame test to tell them apart.
For the powders, I think I got 2 cornstarches, 2 magnesium sulfates, 1 ammonium chloride, and 1 glucose, though I don't remember the exact order. The first powder was cornstarch and the last one was glucose for sure, though.
Other things if you're interested: We said that Rosenbaum and Crittendon worked together to commit the crime, determining that from the evidence and also because the scenario said that they were known accomplices of each other. We identified the crime scene fiber as polyester, and the fiber found in one of their cars (I can't remember who) was also polyester. The unknown liquid was identified as kerosene from the gas chromatography, and the kerosene container had two fingerprints on it, which matched both of theirs. For the blood spatter question, we said that it hit at an angle of 30-45 degrees. I almost wrote on the case while trying to figure it out, but my partner fortunately stopped me; otherwise, we probably would have been DQ'd. (It was annoying that we couldn't write on the case at all; I wanted to take notes on it.) For the DNA question, I think we put down that it identifies Annie? (I don't remember her name, but the victim was female) Necessary as a victim only.

[Steelfoam]

I also got 1 glucose, and 2 cornstarch, at least one mgso4 but i think i got sucrose for one... i always get mgso4 and ca(no3)2 confused, we only got 6th.... no idea what my partner did at state.... we'll have to work wayy harder at nationals

[Phenylethylamine]

Does anyone have a good way to tell the difference between MgSO4 and Ca(NO3)2 besides the flame test.

Magnesium sulfate forms a white precipitate with NaOH (so dissolve some of the powder in water in your well plate, and put a couple drops of NaOH in there. If it's magnesium sulfate, you'll immediately see a pretty unmistakable white precipitate form; if it's calcium nitrate, nothing).