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forgottenpassword
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Quote: Originally posted by Zyklonb  | | I just fond out that Walmart and Kroger has solid carbon dioxide. Not sure if you can get it, but it's quite easy to find, and much colder than ice
water with a chloride salt. |
I'm sure I could find it somewhere, but how long would it last? I assume that I
couldn't store it for any length of time. -40 C is not too bad and the ingredients are easily acquired and stored. I imagine that most reactions done
at -78 C could also be done equally well at -40 C. Perhaps addition rates would have to be lowered slightly but that's not much of a problem.
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Zyklon-A
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| Quote: Originally posted by forgottenpassword | | Quote: Originally posted by Zyklonb | | I just fond out that Walmart and Kroger has solid carbon dioxide. Not sure if you can get it, but it's quite easy to find, and much colder than ice
water with a chloride salt. |
I'm sure I could find it somewhere, but how long would it last? I assume that I
couldn't store it for any length of time. -40 C is not too bad and the ingredients are easily acquired and stored. I imagine that most reactions done
at -78 C could also be done equally well at -40 C. Perhaps addition rates would have to be lowered slightly but that's not much of a problem.
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I have not handled dry ice much, depending on the size of the block and where you store it, it should last for hours.
See this:http://www.eatbydate.com/other/dry-ice/
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MrHomeScientist
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If you have it in a well-insulated container as a large solid block (as opposed to small pellets), it can last a day or two. I've had success with a
cooler packed with bubble wrap and taped closed with duct tape. Don't put it in a tightly sealed container of course, because of pressure buildup!
I've heard it's a bad idea to store it in your freezer too, because the pressure increase can damage the fridge or pop the door open. Technically you
can handle it without insulating gloves as long as you keep it moving around, but I really don't recommend it.
On topic, my favorite reaction of all time is the barking dog. I've done the 'real' version with carbon disulfide many times, but when the sulfur
dioxide gas it produces started bothering my throat I switched to a safe version. It replaces the CS2 with methanol and boric acid. This
changes the flame color to green, and seems to greatly speed up the reaction too. Woelen and I talked about it in a thread somewhere, and credit to
him for the idea.
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nb198
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| Quote: Originally posted by thesmug | | Mercury thiocyanate decomposition with heat, thermite (FeO and Al powder). So hard to choose between the two! |
Hey, I made a synthesis video about the mercury thiocyanate! Maybe you'll like it.
Link
[Edited on 25-3-2014 by nb198]
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Brain&Force
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| Quote: Originally posted by thesmug | | Mercury thiocyanate decomposition with heat, thermite (FeO and Al powder). So hard to choose between the two! |
Really, FeO/Al thermite suits you? I'm into more exotic thermites, especially Al/MnO2.
There's this one luminous clock reaction which is really unusual. I believe it was on the Periodic Table of Videos channel. I myself haven't seen too
many cool reactions, but I'd like to burn ytterbium and samarium, produce reduced europium compounds, and perform the iodine clock reaction. Or better
yet, invent a new type of clock reaction.
Of the reactions I have seen, I particularly like the chemical chameleon with peroxide and burning magnesium. Copper complexation is also quite
interesting.
At the end of the day, simulating atoms doesn't beat working with the real things...
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Zyklon-A
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Copper oxide thermite, copper carbonate thermite and copper sulfate thermite (all with aluminum as reducer.)
Copper metal flash powder: 4Cu + KClO4 → 4CuO + KCl.
I haven't done this one yet, but Botanist told me about it, and I will do it whenever I can get more copper sulfate. (To make copper powder:
CuSO4(aq) + Al → Al2[/sub(SO4)3 + Cu.)
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Texium
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| Quote: Originally posted by Zyklonb |
I haven't done this one yet, but Botanist told me about it, and I will do it whenever I can get more copper sulfate. (To make copper powder:
CuSO4(aq) + Al → Al2[/sub(SO4)3 + Cu.) |
Yeah, we did a series of copper related reactions in chemistry class for our midterm lab, starting with copper wire, and eventually ending with copper
powder by that method, except we used zinc instead of aluminum to replace it. That was pretty cool, and one of the reasons that I decided to start
doing my own experiments. Even though I've always been interested in chemistry, that lab probably catalyzed my decision to do more than just read
about it.
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DraconicAcid
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| Quote: Originally posted by zts16 | | Yeah, we did a series of copper related reactions in chemistry class for our midterm lab, starting with copper wire, and eventually ending with copper
powder by that method, except we used zinc instead of aluminum to replace it. |
Does every college/university in North America do a version of that lab? I've attended two and taught at four, and I don't recall any college not
doing that one...
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Texium
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Well maybe so, but this is in high school!
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Steam
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Probably the decompression of Iron Oxalate under heat, then poring out the pyrophoric iron!
or the reaction of bromine with aluminium!
DISCLAIMER: The information in this post is provided for general informational purposes only and may not reflect the current law in your jurisdiction.
No information contained in this post should be construed as legal advice from the individual author, nor is it intended to be a substitute for legal
counsel on any subject matter. No reader of this post should act or refrain from acting on the basis of any information included in, or accessible
through, this post without seeking the appropriate legal or other professional advice on the particular facts and circumstances at issue from a lawyer
licensed in the recipient’s state, country or other appropriate licensing jurisdiction.
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Nitro-esteban
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Probably burning potassium picrate or a mixture of ammonium perchlorate, charcoal, and sodium benzoate. For some reason it burns with a very bright
yellow flame.
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Oscilllator
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The other day I ate some methylene blue. It turns your urine an incredible bright blue-green colour!
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thesmug
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How much, Oscillator?
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sasan
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Try CS2 vapors and N2O gas in a measuring cylender
Very beautiful and produce a very nice blue light
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Mailinmypocket
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The Beloisov-Zhabotinsky reaction can be absolutely amazing when done with exactly the right concentrations/dyes to make growing concentric rings.
Disturbing the system with a toothpick causes entirely different patterns to occur almost organically.
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kecskesajt
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P-nitroaniline and hot H2SO4.
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Mailinmypocket
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I forgot about that one! Got some aniline coming so perhaps a small synthesis of p-nitroaniline is in order 
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careysub
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| Quote: Originally posted by MrHomeScientist | | If you have it in a well-insulated container as a large solid block (as opposed to small pellets), it can last a day or two. I've had success with a
cooler packed with bubble wrap and taped closed with duct tape. |
The best cheap commonly available insulations I am aware of are foil-faced polyisocyanurate (PIR*) rigid panel, and expanded polyurethane rigid panel.
I find the foil PIR panel cheaply in my local Box Box Hardware stores. It would be interesting to takes a sheet of this stuff, cut it up and duck tape
it into a multi-layer dry ice box to see how long a standard dry ice block will last.
*Not an obvious acronym. I don't know why it is not PIC.
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feacetech
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Silver tree is quite nice
silver nitrate and mercury
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j_sum1
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My students always ask for sodium and sulfur. PPE essential. Keep quantities very small (0.05g of Na) and grind in pestle and mortar. Makes 'em jump.
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subsecret
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Burning magnesium, manganese heptoxide and methanol, and decomposition of ferrous oxalate. I also test paint for lead (for my brother's projects), and
I enjoy precipitating lead (II) sulfide with sodium sulfide, after the sample is dissolved in nitric acid.
Fear is what you get when caution wasn't enough.
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unionised
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The coolest reaction I did was when I was a student.
I prepared bis toluene chromium. Cr(C7H8)2
The kit was mainly a large round flask surrounded by liquid nitrogen and containing a tungsten coil and connections so it could be heated by the
passage of an electric current.
I placed a piece of chromium in the coil and evacuated the flask then started to leak a slow stream of toluene vapour into the flask- when it hit the
walls it froze instantly.
I then connected the coil to a power supply and fed about a kilowatt of power into so it glowed white hot- not quite hot enough to melt the chromium,
but hot enough that it sublimed into the vacuum.
On the walls of the flask the chromium and toluene co-condensed to form a greyish mixture.
Once the experiment had run for a few hours (during which my colleague and I poured several gallons of nitrogen into the cooling bath to keep it cool)
I disconnected the power, and let the flask warm up again.
As the toluene melted it reacted with the chromium atoms that were stuck into the frozen matrix to produce the desired Cr[0] complex.
I'd say that the melting point of toluene -95C is pretty cool for working with individual Cr atoms.
[Edited on 7-1-15 by unionised]
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Little_Ghost_again
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Taking a solution of calcium chloride and adding conc sulphuric acid and watching calcium sulphate drop out snow white onto the bottom of the beaker,
it was simple and easy but there was something about watching a solid of one substance start to appear from a liquid of another.
Dont ask me, I only know enough to be dangerous
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franklyn
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Youtube has a wealth of practical demonstrations
http://www.youtube.com/watch?v=FofPjj7v414
http://www.youtube.com/watch?v=0KFAoqODZok
http://www.youtube.com/watch?v=hGn7aSe8e6w
https://www.youtube.com/watch?v=nadpcadav1I
I had the thought what would one of those color changing ' clock ' mixtures look like if it were to be made into a sudsey foam.
This is remarkable for the ease of preparation of a non-Newtonian fluid.
http://www.youtube.com/watch?v=_0J4dRqg7CE
Casein extraction from milk. Here's a thought, what about mixing this with the starch made above. Bullet proof properties ? Hmm.
http://www.youtube.com/watch?v=VFvik_THcNQ
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Mailinmypocket
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I thought the oscillating foam idea was too cool to not attempt. The first attempt was a fail, it was the Belousov-Zhabotinsky reaction with ferroin
as the indicator. On a test tube scale both reagents were prepared and in one tube was added half a drop of Sunlight soap. After mixing both reagents
together the tube was sealed and shaken violently to create suds. The mix stayed red but did not change colors, it did however do the usual slow
production of bubbles accompanied by the bromine odor.
Another attempt was done but this time using methyl cellulose to thicken the mix and hopefully get color changing foam. It seems to work. A lot of
ferroin is needed to make the bubbles appear colored and foam is really hard to produce even by shaking the tube hard... (Methyl cellulose isn't soap
after all) The color changes aren't very dramatic either. Now having had some success I'll try and tweak the mixes to see if something else works
better and post some pictures or video! Neat idea Franklyn!
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