hermanntrude

every time i write "µ" i remember that it's the right thing to do and feel a little smug and smile to myself. That way, I don't mind the extra effort. On a more serious note, though, the amount of biologists who, when asked a simple question involving a microliter, havent a clue what you mean but immediately get it when you say "you-ell" drives me nuts.

a gold-coloured pen? what is a 5 rupee coin made of?

here's the patent: it describes what the candles are made of http://www.patentstorm.us/patents/6712865/description.html it's mostly trimethyl citrate, apparently, with metal salts and/or complexes and pigments

some blue flames come from hydrocarbon fuels when burned in very specific conditions (like the blue flame of the bunsen burner with the chimney open). perhaps the candle was made of an unusual hydrocarbon? You are correct that a coloured flame can also come from metals... sulfur will also do it, although it would create sulfur dioxide as a product which is harmful... so it probably wasnt that. According to wikianswers.com, you can get a blue flame from arsenic (probably not what you saw), selenium (also probably not), Indium (also probably not... quite expensive) or copper halides. My guess is that the candle you saw had some copper chloride, iodide or bromide in it. as for the solubility, it doesn't really matter. The copper salt could just be sprinkled into the wax in a very fine powder and as long as it was dispersed throughout the wax it wouldnt matter that it didnt dissolve.

I really think the u shouldn't replace the µ. it doesn't even look the same and it often results in people actually believing it's supposed to be a u, and wondering what on earth that funny µ symbol means. it's not hard to type it even if you're not german

Justonium. I won't tell you not to breath hydrogen (although i would strongly advise that you dont) but I will request that you don't try to tell the entire science communinty it's perfectly safe on this forum. We don't want our members blowing holes in their chests or asphyxiating themselves just because you assumed they knew something about safety. This isn't a matter for debate, it is part of our hazmat policy and also simply a matter of common sense.

for your information, there is no such thing as a uL. What you're looking for is a microliter, which can be abbreviated like this: µL To get the micro symbol (greek letter mu), hold down alt and press 0181, then release alt. Or use the character map.

certainly it won't kill instantly but in certain circumstances it could, whereas it's much less likely with helium, which will give identical results.

hehehe i didn't spot that

a responsible chemist doesn't do "stunts". It's not that funny, it can be done ten bazillion times more safely using helium, and it has the potential to kill you in three different ways.

Margel, please read the policy concerning homework help. We don't just give answers outright.

mercury is the only pure liquid metal at 25°C, but at 29°C, gallium melts, and if you make alloys, there are several ways of making metals which are liquid at room temperatures. Gallium particularly will wet glass... now why would it do that when mercury doesnt?

gallium and indium in the molten state and also galinstan all wet glass, but not plastics... this means they're behaving a bit like a polar liquid... but a liquid made of an element cant be polar, can it? so what causes gallium to wet glass but not mercury?

I still think this is a bad idea. Anyone who does chemistry has a responsibility to the general population (particularly the less well mentally endowed) to show them that putting things from your lab into your mouth is not wise. never inhale, eat or drink any substance in or from a laboratory, even if it is pretty safe. And inhaling an incredibly flammable substance like hydrogen isn't entirely safe anyway.

I've seen others use it here and I now make it a habit of answering this type of question with this type of link. It certainly wasnt my idea but it teaches an important lesson.

It does say to estimate it, rather than calculate it. try this: work with a hydrogen-hydrogen bond. what is the length of it? how many nodes are there between the nuclei? given the number of nodes, how big is the wavelength? are most bonds longer or shorter? by how much? I may be going down the wrong route but that's how I'd approach it.

is the mouse trap provided or can you select one? because there are "mouse" traps which are designed for rats, and they have much more powerful springs

my apologies. I didn't read the original post. If you intend to breathe the stuff, buy it ready made in lecture bottles and buy the extra-extra-extra pure expensive stuff. or preferably don't do it. Generally, as a rule, chemistry professionals don't breathe, eat, smoke or otherwise consume anything they've made. At the very least, it's a bad example.

any kind of hot metal placed in water (or aqueous solutions), even unreactive ones, can explode. goggles or safety glasses, and/or an explosion screen would be advisable.

welcome to the forum. Chemsiddiqui has answered your query pretty much perfectly, i think. Another way to answer it would have been to google the name.

just as a warning, anyone who wants to try this should be aware that chlorine gas is extremely dangerous. Do this in a fume hood, or preferably, not at all.

generally, in my experience, when the product is (a) unexpected and (b) black, it means it's most likely some crappy decomposed mixture of crap, not worth putting a name to. for crying out loud please give up on the sodium thing. sodium hydroxide wont help either. It's dangerous and incredibly difficult. and you obviously don't have the necessary experience. I'm a chemistry instructor with a PhD in nanomaterials and I would try it either.

rofl nice one

it's very hard to reduce sodium. organic solvents are nearly all flammable, so dont try putting a current through them, and bear in mind that a LOT of other reactions will occur before sodium will accept that extra electron... perhaps a few you (or I) havent heard of. Also bear in mind that if it was that easy to make sodium in that way, people would do it all the time.

i'm not sure about your calculation, but electrical input energy and Gibb's free energy aren't the same thing, as far as I know. I may be wrong, however