| Author | Message | ||
     Justin |
If I buy the Gallium in your catalog section will it coat the sides of the vile or will i be able to see it splash around like murcury? | ||
| Simon Quellen Field (Sfield) |
It coats. | ||
| Justin |
If i leave it sit again will it all go to the bottom again like it is in your picture? | ||
| Justin |
What happens if I let it set, will it run back down the vile like it is in your pictures? | ||
| Justin |
oops, sorry for the double post. | ||
| Simon Quellen Field (Sfield) |
No, it stays there. You might be able to remove the metal, and scrub the glass clean, then coat the glass with something the metal will not stick to, perhaps a silicone oil or grease, or maybe vaseline. I have not tried this, so I don't know if it will have the desired effect. One of the nice properties of Gallium and Indium is that they stick well to many things, such as glass and plastic. This makes them good for making electrical connections, and for sealing glass-to-metal joints for vacuum work. | ||
| Justin |
How many grams are there of Gallium are in a single vile? And how much is there of The Gallium alloy? | ||
| Simon Quellen Field (Sfield) |
We don't specify a weight or a volume. The vials are filled by hand, and there is some variation. The alloy vials are filled nearly to the top of their 1/2 dram vials. The Gallium is filled about halfway in their 5/8 dram vials, since it may solidify in transit, and we don't want the expansion of the metal to break the glass. | ||
| Justin |
Wait, one dram is only equvilant to 1.7718 grams. That means ½ a dram vial is only about .9 grams. It looks like there is more than that. Are you sure the vials are measured in drams? | ||
| Justin |
Ah, I found your viles on ebay, you are right. Anyway, What if I fill a jar with mineral oil, then ad the metal? Would the metal mix up or woult it stick together and roll around the jard submerged in the oil? sorry for all the questions. | ||
| Simon Quellen Field (Sfield) |
A dram is a unit of volume, not weight. A dram of some substance might weight 1.7718 grams, but a dram of metal is likely to weigh more. I just weighed a bottle here in my office, and bottle and all was 16.5 grams. Other bottles will vary. The metal will not mix with the oil. But it may still coat the glass. You will have to experiment. | ||
| AnotherAnonymous Unregistered guest |
I weighed the gallium in such a vial, it was 12.3 grams (not bad for $24). The vial was a little too full and it cracked after the first melting, but no harm no foul (I got to play with it for a few hours separating glass from gallium, yay) | ||
| Anonymous |
I read online that the way they make galinstan (the liquid metal sold here) not stick to the sides of glass galinstan thermometers is they coat the glass with a thin layer of gallium oxide. Any idea if we can get vials coated with gallium oxide or coat some glass ourselves? | ||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 308 Registered: 12-2004 |
Sputtering gallium oxide onto glass is not a project I can recommend for my typical reader. However, you might try some wax or floor polishes, or some Teflon spray. | ||
| kool aid man (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
can you make the alloy into little blobs that roll around like mercury? and can you combine the blobs to form one big blob? | ||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1578 Registered: 12-2004 |
Sure. But since it wets what it touched (unlike mercury), you will get gray marks on your hands. | ||
| Kool nAid Man (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
can u wash off the marks easily? (just wondering) | ||
| Orange Sharpie (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
Kool Aid Man's post gave me an idea. Would it be possible to use the alloy to build a mercury maze? (this is kind of like a PSP game i played a few weeks ago) | ||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1582 Registered: 12-2004 |
It washes off easily. The mercury maze was originally a real toy made using mercury. We don't make toys out of mercury anymore. ;-) Yes, you can use any liquid metal, if you make sure the substrate is something to which it will not stick. | ||
| orange sharpie (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
thanx a bunch! | ||
| BigTv (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
waht kinds of surfaces would the alloy not stick to? | ||
| daxter (Unregistered Guest) Unregistered guest Posted From: 68.42.96.146 |
maybe if you use some kind of wax like pinball playfield polish it wouldn't stick if you waxed it reguarly. | ||
| Chris DeArmitt (Unregistered Guest) Unregistered guest Posted From: 62.214.197.200 |
You asked about stopping the metal from sticking to the glass. I would suggest that you coat the glass with an alkyl silane. This will react onto the glass to form a monolayer that the gallium should not wet. It's easily done. For example http://www.sigmaaldrich.com/catalog/search/ProductDetail/FLUKA/40242 Chloro(dodecyl)dimethylsilane CAS 66604-31-7 Make a 1% mixture of that in heptane, hexane, or similar and add it to the flask. The silane will coat the glass in a transparent monolayer. | ||
| Eamon Keane (Cimon9999) New member Username: Cimon9999 Post Number: 1 Registered: 9-2008 |
Hi, I'd like to buy some of your Gallium, it's still for sale, right? I'm wondering what the %purity is, though? I don't need 99.999999% but 99.9% or 99.99% perhaps? How come you guys can make it so cheap, it seems everywhere else wants to charge me like $1000 for 50 grams!!! Thanks, Eamon | ||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1911 Registered: 12-2004 |
We sell toys, not laboratory reagents. Since the vials are hand filled, and we don't test them after filling, we make no purity claims. You did not indicate what your application was, or what purity you require, but we do not add anything to the gallium we receive from commercial wholesalers. Our prices are lower than what you are seeing elsewhere, by about three or four times, likely because we buy in much larger quantities. | ||
| Eamon Keane (Cimon9999) New member Username: Cimon9999 Post Number: 2 Registered: 9-2008 |
Thanks for the quick reply. Well what I'm looking into is the use of an Aluminium-Gallium compound to react with water to evolve hydrogen. The hydrogen is then used to power a car. The Gallium prevents an oxide layer from forming on the surface of the Aluminium and it's the lack of this layer which allows Aluminium to react with the water. That's the science part! We're kind of following in the footsteps of the folks at Purdue University who've been looking into this for a while. They believe that the %purity of Gallium isn't overly important ie we don't need the super rarefied version used in the semiconductor industry. If you could find out what the commercial wholesaler quotes it as, that would be helpful. I'm sure it's something like 99.9%, that's the lowest quality I can find on the internet! Thanks | ||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1912 Registered: 12-2004 |
See the last two paragraphs of "http://sci-toys.com/scitoys/scitoys/thermo/liquid_metal/liquid_metal.html" | ||
| Theresa Simmons (Theresa) Advanced Member Username: Theresa Post Number: 67 Registered: 1-2008 |
By the way, adding a little sodium hydroxide to the water would be thousands of times cheaper than using gallium. | ||
| Eamon Keane (Cimon9999) New member Username: Cimon9999 Post Number: 3 Registered: 9-2008 |
Simon: Thanks for the info, that's something to ponder all right! It seems I've fortuitously stumbled across someone with detailed knowledge of Gallium! Hopefully you can help me out a bit. The project is basically to investigate what Jerry Woodall has been doing at Purdue, and we haven't started yet. So you're saying Gallium will melt a hole in Aluminium? Well what we're trying to replicate is the patent obtained by Woodall: http://www.google.com/patents?id=Ic6oAAAAEBAJ&dq=power+generation+from+solid+aluminium In it he formed an 80/20 Al-Ga by heating the mixture up to 600degrees C and then cooling it back down. It formed a solid compound which was stable at room temperature. When placed in water it reacted fully to evolve hydrogen. The reaction is (according to a textbook): 2Al + 3H20 --> 2Al(OH)3 + 3H2 -199.6kcal Woodall says the gallium component is "inert" allowing it to be recovered and reused. Is it inert? How pure would it be? Is it recyclable, and would you have any insight into how you might recycle it? Thanks for your time, I appreciate it. | ||
| Eamon Keane (Cimon9999) Junior Member Username: Cimon9999 Post Number: 4 Registered: 9-2008 |
Theresa: That's a good point, something I wasn't aware of. The reaction as google understands it is: 2Al + 2NaOH + 6H20 => 2NaAl(OH)4 + 3H2 Is that correct? Does it matter if the Aluminium has a passivation layer (ie a thin surface layer of Al2O3) or does the reaction happen regardless? I couldn't really find an answer to that on google. At any rate, this Gallium is what's supposed to disrupt the passivation layer that forms on Aluminium when inevitably it's exposed to Oxygen. Additionally is the Aluminium recoverable from the NaAl(OH)4? This is one of the key things with using Gallium because when just Aluminium and Gallium are used, Al(OH)3 is formed and this is crucial to the energy balance because it takes much less energy to produce this than to produce pure Aluminium from the original Bauxite ore. Thanks for your insight, Eamon | ||
| Theresa Simmons (Theresa) Advanced Member Username: Theresa Post Number: 68 Registered: 1-2008 |
Are you actually planning to add the energy back in order to get the aluminum back into metallic form? That is much more ambitious. You can use any strong base or strong acid. Hydrochloric acid will work fine, and the aluminum chloride is not difficult to turn back into aluminum. You just melt the salt and run a current through it in the absence of oxygen. The aluminum oxide layer is removed by either a strong base or a strong acid, you don't need gallium. And zinc might be cheaper than aluminum, and much easier to get back into solid form, since you don't need the molten salt, just run an electric current through the resulting solution and the zinc will plate out. You can get hydrochloric acid at a pool supply store. Sometimes they call it muriatic acid (using the archaic name for some reason). Zinc you can get at a marine supply store (boating), as it is used for protecting copper rudders from oxidation. Or you can just use galvanized nails -- the coating on them is zinc. | ||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1913 Registered: 12-2004 |
Read the last part of the gallium page. It is easy to reproduce. The gallium that is left over will work again and again, as it is not used up or dissolved. It will still have some aluminum in it, but it will work fine. You don't need to heat the mixture. The gallium will form an amalgam with the aluminum just fine at anything above gallium's melting point, which means any hot day. But aluminum and an acid is lighter in weight (something important for transportation) and much cheaper, and will react as fast as you want it to (by controlling the dilution of the acid). And the hydrogen produced in this way is still much more expensive than gasoline or diesel fuel. | ||
| Anne Archibald (Unregistered Guest) Unregistered guest Posted From: 132.206.92.205 |
Has anyone tried that silane coating idea? (Incidentally, supposedly the gallium/galinstan itself is not wetting but the oxide is. Not a very important distinction unless you're working under inert gas.) |
