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Re: Crime Busters B
Posted: April 6th, 2013, 12:31 pm
by theriddler
stephritz929 wrote:We definitely saw a reaction; it wasn't a big one, but it was a reaction. We have the same problem with our Iodine and H202. No reaction when practicing but at regionals there was a definite reaction.
Was it delayed? If so, do you recall the approximate time between when the HCl interacted with the aluminum and the time of the fizz?
kind of like the incubation period
Re: Crime Busters B
Posted: April 6th, 2013, 8:38 pm
by piimasta314
I suppose it all depends on what your materials are. Maybe your school HCl is diluted so that students not used to pouring chemicals won't end up in the emergency room if they splashed themselves. Or the aluminum you used wasn't as pure (if you just pulled it off a regular soda can or food tray I'm pretty sure that there's other stuff mixed in there that will make it less reactive to the environment in general.)
Re: Crime Busters B
Posted: April 6th, 2013, 8:42 pm
by stephritz929
theriddler wrote:stephritz929 wrote:We definitely saw a reaction; it wasn't a big one, but it was a reaction. We have the same problem with our Iodine and H202. No reaction when practicing but at regionals there was a definite reaction.
Was it delayed? If so, do you recall the approximate time between when the HCl interacted with the aluminum and the time of the fizz?
kind of like the incubation period
The best way to tell is to compare it to a reaction with Zinc. Zinc, for us at least, bubbled within seconds, and they were rather larger bubbles. With Al, probably within the first 20 seconds tiny tiny tiny bubbles began to appear, but after letting it sit untouched for about a minute the entire sample was covered in tiny bubbles we almost didn't realize were there. we could "remove" the bubbles off of the aluminum like how you can with your finger wipe away condensation off a cup. or if you have something that you put in water, and it gets bubbles on it, those tiny rows of bubbles..this is beginning to not make much sense but that's basically what it looks like lol. cover the ENTIRE piece of metal in HCl, let it sit while you do other things, then look back and there should be tiny bubbles.
Re: Crime Busters B
Posted: April 6th, 2013, 8:44 pm
by piimasta314
Anyway, aluminum is supposed to react with HCl and produce hydrogen gas. I suggest you look up an activity series chart on google images or something. You don't have to understand it yet; just know that anything above hydrogen will react with HCl to form hydrogen gas.
It goes: Lithium, Potassium, Barium, Calcium, Sodium, Magnesium, Aluminum, Manganese, Zinc, Chromium, Iron, Cobalt, Nickel, Tin, and Lead.
Lithium will react most violently...lead will not react as easily.
Aluminum as you can see is in the middle so it might take more time to react, but it's supposed to.
Re: Crime Busters B
Posted: April 11th, 2013, 1:24 pm
by caseyotis
I'm stuck. States is tomorrow and I have 1/4 of a page to fill on my cheat sheet. I have fingerprints; pictures of fibers; charts for metals, liquids, and crystal/powders; and plastics. .-. I also have the section on how to write a good analysis. What else should I put on?
Oh, and don't bother responding after today.

Re: Crime Busters B
Posted: April 11th, 2013, 2:02 pm
by geminicross
Chromatography Steps may be good if you need em
or this
Re: Crime Busters B
Posted: April 11th, 2013, 2:06 pm
by caseyotis
Nah, I don't need those.

Re: Crime Busters B
Posted: April 11th, 2013, 5:22 pm
by piimasta314
put weird trivia stuff like scientists that came up with the processes...also if you don't have uses for the various powders and polymers or whatever you should put those too. You never know what they might ask for tiebreakers.
Re: Crime Busters B
Posted: April 11th, 2013, 6:11 pm
by bam
caseyotis wrote:I'm stuck. States is tomorrow and I have 1/4 of a page to fill on my cheat sheet. I have fingerprints; pictures of fibers; charts for metals, liquids, and crystal/powders; and plastics. .-. I also have the section on how to write a good analysis. What else should I put on?
Oh, and don't bother responding after today.

You could also include: parts of a hair; blood spatter information; uses of all the metals, powders, liquids, and plastics.
There's really not much else except for random facts for States....
Re: Crime Busters B
Posted: April 11th, 2013, 6:24 pm
by caseyotis
bam wrote:caseyotis wrote:I'm stuck. States is tomorrow and I have 1/4 of a page to fill on my cheat sheet. I have fingerprints; pictures of fibers; charts for metals, liquids, and crystal/powders; and plastics. .-. I also have the section on how to write a good analysis. What else should I put on?
Oh, and don't bother responding after today.

You could also include: parts of a hair; blood spatter information; uses of all the metals, powders, liquids, and plastics.
There's really not much else except for random facts for States....
Uses? Eh, I printed out the cheat sheet already. .-. Those things are my partner's responsibility, and he said he didn't want that on the cheat sheet. I don't really care at this point.