DFliyerz
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Registered: 22-12-2014
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Gallium and Silicon-containing Alloys
Earlier I was cleaning some gallium off of my ceramic hot plate with aluminum foil, and I noticed it was disintegrating very quickly from the alloy
forming. I then decided, on a whim, to toss this disintegrated aluminum foil into a beaker full of water to generate hydrogen, just for fun. However,
this is where it got interesting. Unlike the normal reaction of water with aluminum-gallium alloy (ie a heat sink), which just produces hydrogen, I
noticed that occassionally there was a very sharp "crack" coming from the beaker, extremely reminiscent of silane detonation from the reaction between
magnesium silicide and an acid. This would make sense, since aluminum foil normally contains around 0.65% silicon in the alloy. This makes me think
that either some form of gallium silicide which can react with water is forming, or that somehow the gallium-aluminum alloy alloys the silicon to
react with water. Does anyone have any ideas about this?
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symboom
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Damn I have boron and gallium no silicon
Wheres my gallium
magnesium silicide and hydrochloric acid are used to generate
Silane gas im sure its gas trying to escape and its traped underneath the alloy
Mercury, thallium, bismuth, and lead are immiscible with liquid silicon.
[Edited on 20-7-2017 by symboom]
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Melgar
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3040 aluminum contains a significant amount of magnesium, and it's commonly used for stuff that comes in contact with food.
I actually had a few pieces of a scrap silicon microchip wafer, and some gallium too, so I tried getting them to alloy. Not easy, what with the
silica layer. So I covered them with mineral oil, broke up the silicon under the oil, using a rod, then stirred them around to see if they'd alloy.
They actually did, but then the gallium froze. So I applied heat, and they melted together a little, but then froze again. Further heating resulted
in white vapors from the mineral oil. Seeing as gallium can expose aluminum's surface increasing its reactivity, I wondered if it did the same for
silicon. I added some iodine. No reaction at first, but on heating, there was a definite exothermic reaction that produced a brown-colored substance
with similar properties as elemental iodine. Exposure to air resulted in white and yellow vapors. It seemed like it might just be the elusive
silicon tetraiodide (95% iodine by mass), which forms silica and hydrogen iodide on exposure to water. Guess the DEA will have to make two more
elements illegal now, eh?
Next, I tried heating silicon and gallium in a test tube, but as soon as they alloyed, the mixture solidified. I got it to red hot, but still solid.
I added aluminum to see if that changed anything. Still solid. I'd add water, but if there's a chance it could make a loud noise, I'm definitely
going to wait for my roommate to leave.
The first step in the process of learning something is admitting that you don't know it already.
I'm givin' the spam shields max power at full warp, but they just dinna have the power! We're gonna have to evacuate to new forum software!
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