Chunk of gallium melts in your hand


#14

Yeah, I’m sorry for jumping straight into what could be construed as “terror mode” or whatevs. That said, I was, frankly, amazed at how quickly the stuff acted and with so little visible change or activity. I could see some small “crinkling” in the surface of the can as the gallium did its thing, but nothing that would construe the actual damage being done to the structure of the thing. I’d heard about the low melting point previously, but that structural decay is very cool.


#15

nah, I wrote it tongue-in-cheek and you should read it with this intention. I should have added “except I’m far away” or something similar.


#16

Gallium is pretty damn safe.


#17

Certainly not the TSA! If they were all that was standing between us and air terror, planes would be falling from the sky every week from gallium induced structural failure.


#18

Yes. Elemental Mercury doesn’t have missing electrons and therefore is fairly nonreactive. It’s the mercuric compounds we need to be exceedingly careful with. A Chem researcher was wearing two layers of nitrile gloves and mere drops of the dimethylmercury went right through them and killed her.


#19

Hmm, TSA reminds me of this. Is Gallium for flight-security purposes a liquid?


#20

A famous case. And not the only one.

There had been previous documented cases of death due to dimethylmercury poisoning. In 1865, two English laboratory assistants died several weeks after helping to synthesize dimethylmercury for the first time. In 1972, a 28-year-old chemist in Czechoslovakia had suffered the same symptoms as Wetterhahn after synthesizing 6 kg of the compound.

Hg(CH3)2 is one of the couple things that give me willies.
Imagine six kilograms of the thing.
In a glass bottle.


#21

Crazy and sad.


#22

Done as requested. You lucked out by catching me not sleeping yet. Early day tomorrow.


#23

Thank you! As a favor back, & in the Maker spirit, I disassembled a Swiffer today and scavenged a nice micro switch, battery leads and wire, a little motor and this cool one way valve attached to a syringe needle, which was for letting the air back into the cleaning fluid bottle after it squirted out onto the floor. Pretty cool takedown.


#24

Sends an absolute chill down my neck and spine. All it would take is some of that stuff seeping into the hull. Bwwwwweeeweweww.


#25

Gallium: It melts in your mouth and in your hand!


#26

My understanding was that it was a US federal offense to take gallium on an aircraft. I don’t have a reference, so I’ll just say “the internet told me.” :wink:


#27

Is gallium a catalyser or is it “used up” when reacting with aluminium (too lazy to look it up)?


#28

I don’t know. I’m a data nerd not a physical sciences weirdo. Shaddack, Meeshak, or Abednego, care to shed light here?

Edit. Wait. @Mindysan33!!! I’m pressing the Mindy button.


#29

I’d dare to. But I’d package it in a small pipebomb-like steel container that it would not escape from even in a plane crash. (Todo: check if gallium wets and embrittles ferrous alloys.)

It dissolves in the aluminium. (It also breaks the passivation so you can react the aluminium off with water and recover the less reactive gallium. (I think. Would have to check.)

I have problems with my delta 3d printer. The head waves along the z-axis during horizontal travels. I am taking more naps than grampa Simpson these days which interferes with work and slows it down but will try to address it.


#30

Very interesting, thanks!


#31

Just don’t take it on a plane… seriously gallium amalgams with aluminium are scary:

For much the same reason, mercury is banned from aircraft.


#32

Sounds like misconfig in the firmware. If it’s not a physical defect, I’d start playing there because it sounds like 1 or 2 motors are traveling at different rates that the other(s). I mention physical defects because those vertical bearings can sometimes be sticky so if you have one sticky one but the motors are calibrated fine then you can still have an issue. Upshot; one of these things is not like the other.


#33

Gallium seems alright to fiddle with a bit, but all the talk of dangerous substances reminded me of Derek Lowe’s Things I Won’t Work With series.

A bit from his piece on peroxides:

But I have to admit, I’d never thought much about the next analog of hydrogen peroxide. Instead of having two oxygens in there, why not three: HOOOH? Indeed, why not? This is a general principle that can be extended to many other similar situations. Instead of being locked in a self-storage unit with two rabid wolverines, why not three? Instead of having two liters of pyridine poured down your trousers, why not three? And so on – it’s a liberating thought. It’s true that adding more oxygen-oxygen bonds to a compound will eventually liberate the tiles from your floor and your windows from their frames, but that comes with the territory.

These thoughts were prompted by a recent paper in JACS that describes a new route to “dihydrogen trioxide”, which I suppose is a more systematic name than “hydrogen perperoxide”, my own choice. Colloquially, I would imagine that the compound is known as “Oh, @#&!”, substituted with the most heartfelt word available when you realize that you’ve actually made the stuff.