What chemical when mixed with water, it explodes
Chemistry discussion, revision, exam and homework help.
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Re: What chemical when mixed with water, it explodesI hope not. I've searched quite few explosives after this thread. Is that a criminal offence?(Original post by Left Hand Drive)
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Re: What chemical when mixed with water, it explodesDepends on your race(Original post by Rtcw)
I hope not. I've searched quite few explosives after this thread. Is that a criminal offence?
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Re: What chemical when mixed with water, it explodesHaving seen numerous LithAl fires before, I would guess this aswell. Saying that, its really not safe making LithAl fires, they can get pretty explosive if the temp is quite high.(Original post by gingerbreadman85)
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Re: What chemical when mixed with water, it explodesIf you're going to make an explosion, choosing anything sensitive enough to detonate with water is more than a little silly.(Original post by marshal4)
Having seen numerous LithAl fires before, I would guess this aswell. Saying that, its really not safe making LithAl fires, they can get pretty explosive if the temp is quite high.
My assumption (and hope) is that the OP's question was purely academic.
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Re: What chemical when mixed with water, it explodesI'm almost certain the OP is talking about phosphorus pentoxide.(Original post by gingerbreadman85)
If you're going to make an explosion, choosing anything sensitive enough to detonate with water is more than a little silly.
My assumption (and hope) is that the OP's question was purely academic.
We used to use it in vacuum dessicators as it would keep the atmosphere dry. Once someone turned off the tap without disconnecting the water supply first which caused water to be sucked into the dessicator. There was a blast that disintegrated the heavy glass vacuum dessicator.
Fortunately the shield in the fumehood was down.
Then a demo of the explosive properties of phosphous pentoxide in water was demonstrated to everyone before they got to use a vacuum dessicator. A small amount of phosphorus pentoxide was placed in water and the violent reaction observed...
Similarly, phosporus pentachloride reacts violently with water.Last edited by marcusfox; 15-07-2012 at 14:03. -
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Re: What chemical when mixed with water, it explodesThere is an important difference between sodium metal and sodium ions dissolved in water.(Original post by ConnorB)
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Re: What chemical when mixed with water, it explodesahh. i was always terrible at Chemistry. I learn't covalent bonding through 21 Jump street.(Original post by gingerbreadman85)
There is an important difference between sodium metal and sodium ions dissolved in water. -
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Re: What chemical when mixed with water, it explodesSodium in metal = elemental sodium (highly reactive)(Original post by ConnorB)
ahh. i was always terrible at Chemistry. I learn't covalent bonding through 21 Jump street.
Sodium in water = sodium ion (extremely stable)
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Re: What chemical when mixed with water, it explodesI'm just asking this question because I went to Uni's open day and one of lectures, they showed this reaction. The lecture is not about teaching but showcasing what you can do with chemicals. Explosion is just one of them.
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Re: What chemical when mixed with water, it explodesSounds awesome, what Uni?(Original post by Rtcw)
I'm just asking this question because I went to Uni's open day and one of lectures, they showed this reaction. The lecture is not about teaching but showcasing what you can do with chemicals. Explosion is just one of them. -
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Re: What chemical when mixed with water, it explodesYeah, as if Braniac was real. They didn't use rubidium and caesium, they faked the effect with conventional explosives.(Original post by cuckoo99)
strange that your teacher didnt simply use a group 1 metal in his expierment. rubidium can blow a whole in a bath tub
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You know why? When you drop those into a bath full of water, they are so reactive they jump back out. Nothing like the explosion that we saw on TV, which was probably dynamite.
Actual rubidium dropped in water.
Actual caesium dropped in water.
And when the ampoules are broken underwater...
Rubidium
Caesium
You get better bangs with large lumps of sodium.Last edited by marcusfox; 16-07-2012 at 01:34. -
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Re: What chemical when mixed with water, it explodesPart of the issue with rubidium/caesium is that they are TOO reactive, not enough hydrogen gas builds up before the flame kicks in to give a good bang.
Also, they have very high molecular weights, which means per volume you get less atoms (caesium is 2x the density but over 6x the RAM of sodium), and less atoms means less gas produced.
Furthermore they are considerably more expensive.
Nice big chunk of sodium gets the job done! -
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Re: What chemical when mixed with water, it explodesGuess the op's seen sodium and water reactions at school already though.
The lecturers options increase if he cheats and uses hydrogen peroxide.
Unis are buggers for putting on open day demos that make courses look more exciting than they actually are. manchester electrical engineering had a linear induction motor firing daggers across the room. Needless to say the actual courses are always going to be a great deal more boring. -
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Re: What chemical when mixed with water, it explodesYup, I have already seen most of group1/2 metal reactions. They are nothing like what I've seen at Uni.(Original post by Joinedup)
Guess the op's seen sodium and water reactions at school already though.
The lecturers options increase if he cheats and uses hydrogen peroxide.
Unis are buggers for putting on open day demos that make courses look more exciting than they actually are. manchester electrical engineering had a linear induction motor firing daggers across the room. Needless to say the actual courses are always going to be a great deal more boring.
If I ever get into this Uni, I'll ask lecturer what chemical he used. -
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Re: What chemical when mixed with water, it explodesIf the OP emails the chemistry department of the university involved, showing his interest and asking for more information, I'm sure they would be delighted to provide further information to satisfy his (and ours) curiosity.
However, chances are, the OP will not return to the thread.Last edited by marcusfox; 23-07-2012 at 17:08.
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