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ArcticMyst Security by Avery

Sodium metal

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Mar 13, 2013
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I'm kind of curious what causes it to explode as my test showed there was already a hydrogen flame so it wasn't h2 buildup. I doubt it reached boiling point either.

Btw Na burns beautifully in air but the resultant oxide fumes turn to hydroxide when in presence of water vapor, which means it would be very bad to breathe in.

Did you get tert amyl or butyl alcohol? My 97% t-amyl was still liquid at -12C or so.

I think it melted and touched the water directly with momentum in the oscillation of floating on the hydrogen it's producing.

Interesting video on that subject: Sodium v Water (slow motion) - Periodic Table of Videos - YouTube

BTW a nice little site you have there I enjoyed reading some of your articles
pretty much only dangerous stuff :san:
that's what I like haha ;)
The most dangerous chemistry I've ever done was a very small amount of a hypergolic mixture man that was scary I had every piece of my safety equipment present and still crazy feared of it

Btw If you want to add a C*-20 synthesis to your site PM me
I know a way to make the ß variation of it :beer:
 





Joined
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Well, I started the potassium synth today. Initially I was getting some potassium yield but it only lasted about a half an hour or so that I can tell. I think the steel thermocouple temp probe poisoned the reaction. I think I'm going to have to invest in an electric hot plate and get the temp set to thermal equilibrium and then remove the probe and start the reaction.

It is possible there's still some free K at the bottom but the mixture is so cloudy that I can't see it. My sterno can is running low so I'm just going to let it keep going until the can is out. If I get some, sweet, if no not, no worries. This test was with the impure mineral oil btw, not the "100%" stuff.

Btw, thanks Shokkun. Aye, dangerous stuff usually is the most fun.
 
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Jun 22, 2011
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Got my Sodium sample in the mail the other day. Finally got around to cutting it today. Advertised was 50g in a single square/rectangular ingot, but what I got was two foil-sealed-under-argon 1-oz hexagonal ingots. This is not only a bonus of 9grams but the fact that one ingot can stay in its own seal foil wrapper and the other I can cut up and have fun with.

I opened the one 28.5g ingot today and was surprised to see it was rather oxidized already, with a puplish-grey coating. I quickly cut it in half and then cut off a 3/32" thick sliver to have fun with and put all three sections under mineral oil. The sliver weighed about 0.75g. Immediately upon immersion in oil I saw very small amounts of hydrogen being evolved, likely from dissolved H2O or the 1% mixed tocopherols. It subsided after about 10min.

I sectioned off the 0.75g sliver into several pieces; 0.45g, 0.15g, 0.1g, 0.05g. I began dropping them into water and observing the effect. Below 0.45g the Na would ball up and skirt around on top of the water, with no flame or sputtering. If I blew from several feet away into the reaction vessel a small spark of flame would occur. The 0.45g sample reaction caught me by surprise. I was very glad I had my face shield on! Which is why there is a bit of bad cinematography after the explosion; I had to blow out the burning paper and get the burning Na spatter off my face shield, lol.

I'll have to experiment more with some 0.25g, 0.3g, and 0.35g pieces to see where it goes from unimpressive to holy crap what happened.

I got the same thing, two hex-pieces sealed in bags inside a plastic container. Only weighted the whole container, was about 70g.

In hindsight I should have left one in the bag but I wasn't sure that was better than the oil. Let us know if that's keeping it from oxidizing if you decide to open it eventually.

Mine doesn't seem to bubble much under oil, but it's pretty much white externally and loses the luster after a few days whenever I cut it. OTOH the oxide coat seems very thin, certainly sub-mm.

Well, I started the potassium synth today. Initially I was getting some potassium yield but it only lasted about a half an hour or so that I can tell. I think the steel thermocouple temp probe poisoned the reaction. I think I'm going to have to invest in an electric hot plate and get the temp set to thermal equilibrium and then remove the probe and start the reaction.

It is possible there's still some free K at the bottom but the mixture is so cloudy that I can't see it. My sterno can is running low so I'm just going to let it keep going until the can is out. If I get some, sweet, if no not, no worries. This test was with the impure mineral oil btw, not the "100%" stuff.

Btw, thanks Shokkun. Aye, dangerous stuff usually is the most fun.

Hope you figure it out next time!


BTW: packaged the graphite today, will almost certainly send it to you tomorrow.
 
Joined
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Tried a second round of K synth; this time I noticed that despite sizable H2 production initially, nearly no Mg was consumed. I used dehydrated KOH as well (heated in 215C oil for an hour until murkiness went away). So, a friend I was discussing this with proposed that the MgO present as surface oxidation may cause the formation of MgOH and KO instead of K and MgO as we want.

Not having any cleaner Mg or a ready source for any (other than a questionable purity firestarter tool and nothing to make the shavings with) I decided to try the reaction today with Aluminium (in the form of foil) as the reducing agent instead of Magnesium. Will update will results. So far, it's bubbling away like normal.

Thanks, Atomic! I have the 4NdFeB magnets en route. Will keep you posted on its arrival.

UPDATE 3/1/14:
Potassium synth has failed. I've tried adjusting every variable I could and no yield has been observed in any combination. I suspected moisture content in the KOH was an issue so I began to dry the flakes in an oven and then heat them under mineral oil for two hours at 220C. I suspected the MgO on the Mg powder was causing a side reaction so I started etching the Mg with acetic acid and then thoroughly washing the Mg with water, acetone, IPA, and then water again and then finally drying under a low grade vacuum. I suspected the tocopherols in USP grade mineral oil were degrading and inhibiting the reaction so I sourced some 100% mineral oil. Despite all the changes and varying the temperature between 100C and 225C and trying run times of 1 to 10 hours with periodic teriary alcohol injections there have been no results. I even tried using aluminium as the reduction agent instead of magnesium.

I'll just have to eat the loss and live with it. I'm sure I'll find a use for five kilos of KOH and five ounces of Mg powder.

Btw, I think the hot KOH started to etch the bottom of my Erlenmeyer flash o_O ...
 
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Eh , that sucks . I have yet to even try this reaction but after reading online it seems to be a picky reaction at the best of times .
 
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Tried a second round of K synth; this time I noticed that despite sizable H2 production initially, nearly no Mg was consumed. I used dehydrated KOH as well (heated in 215C oil for an hour until murkiness went away). So, a friend I was discussing this with proposed that the MgO present as surface oxidation may cause the formation of MgOH and KO instead of K and MgO as we want.

Not having any cleaner Mg or a ready source for any (other than a questionable purity firestarter tool and nothing to make the shavings with) I decided to try the reaction today with Aluminium (in the form of foil) as the reducing agent instead of Magnesium. Will update will results. So far, it's bubbling away like normal.

Thanks, Atomic! I have the 4NdFeB magnets en route. Will keep you posted on its arrival.

UPDATE 3/1/14:
Potassium synth has failed. I've tried adjusting every variable I could and no yield has been observed in any combination. I suspected moisture content in the KOH was an issue so I began to dry the flakes in an oven and then heat them under mineral oil for two hours at 220C. I suspected the MgO on the Mg powder was causing a side reaction so I started etching the Mg with acetic acid and then thoroughly washing the Mg with water, acetone, IPA, and then water again and then finally drying under a low grade vacuum. I suspected the tocopherols in USP grade mineral oil were degrading and inhibiting the reaction so I sourced some 100% mineral oil. Despite all the changes and varying the temperature between 100C and 225C and trying run times of 1 to 10 hours with periodic teriary alcohol injections there have been no results. I even tried using aluminium as the reduction agent instead of magnesium.

I'll just have to eat the loss and live with it. I'm sure I'll find a use for five kilos of KOH and five ounces of Mg powder.

Btw, I think the hot KOH started to etch the bottom of my Erlenmeyer flash o_O ...

That is really a disappointment. I guess the purity of the Mineral oil caused a side reaction and reconverted the K into back into KOH or similar...

I was expecting some K from this method. What about using Mg turnings instead?
Also, maybe you could try the thermite reaction to produce potassium instead?
 
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I'm up for trying turnings but have no way of making any, just don't have the tools for it. Nearly out of 100% mineral oil too as I couldn't afford much at $3/Oz.

Got plenty of the 99% though.

In the end there's always electrolysis, but that'll have to wait for when it isn't -28F outside.


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Aha! I might have found the failure point of the K redox method!

Today I did an experiment to test the coalescing ability and alkali metal reactivity of the tert-Amyl alcohol. To my surprise it actually evolved quite a lot of gas and drastically reduced the quantity of free sodium. In addition, it aided in allowing the sodium metal to break up into small globules and actually made it much more difficult to get globules to coalesce! The test was conducted with the following parameters: 1 gram of oxide free pure Na metal was added to de-oxygenated, dehydrated mineral oil. This mixture was heated to 110C. The Na became molten at approximately 100C. Slowly in 0.5ml increments the t-amyl was added with a pipette and the mixture was observed. Once the coalescence inhibition and gas evolution was observed the remainder of the t-amyl (approximately three milliliters) was added and the mixture was gently stirred. The sodium was observed to dissolve into the mixture of alcohol and mineral oil. The Na metal darkened in appearance and evolved gas bubbles. This is the exact opposite of what is expected!!

Lesson learned! Get your organic chemicals from reliable sources! Just because the vial/bottle has a label and says what it is supposed to doesn't mean it is what it says!

If there was any t-amyl in this alcohol it was likely diluted with other alcohols for profiteering.
 
Joined
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Aha! I might have found the failure point of the K redox method!

Today I did an experiment to test the coalescing ability and alkali metal reactivity of the tert-Amyl alcohol. To my surprise it actually evolved quite a lot of gas and drastically reduced the quantity of free sodium. In addition, it aided in allowing the sodium metal to break up into small globules and actually made it much more difficult to get globules to coalesce! The test was conducted with the following parameters: 1 gram of oxide free pure Na metal was added to de-oxygenated, dehydrated mineral oil. This mixture was heated to 110C. The Na became molten at approximately 100C. Slowly in 0.5ml increments the t-amyl was added with a pipette and the mixture was observed. Once the coalescence inhibition and gas evolution was observed the remainder of the t-amyl (approximately three milliliters) was added and the mixture was gently stirred. The sodium was observed to dissolve into the mixture of alcohol and mineral oil. The Na metal darkened in appearance and evolved gas bubbles. This is the exact opposite of what is expected!!

Lesson learned! Get your organic chemicals from reliable sources! Just because the vial/bottle has a label and says what it is supposed to doesn't mean it is what it says!

If there was any t-amyl in this alcohol it was likely diluted with other alcohols for profiteering.

I am happy that you have found the potential problem for the K synth however, I was expecting that you would have been more successful using Mg and
KOH.
At least we know now what the issue is.

I am still trying to track down T-Amyl Alcohol over here...
:thinking::thinking:
 
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No worries. Yeah, I was more hopeful too, but perhaps there is reason why K metal is $500 per troy ounce!

Germane to the thread at hand I'll be dumping this distorted Na / alc / oil out onto the mounds and mounds of snow we have outside at time point tomorrow. If anything interesting happens I may toss a slice of Na on fresh snow and film it!
 
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No worries. Yeah, I was more hopeful too, but perhaps there is reason why K metal is $500 per troy ounce!

Germane to the thread at hand I'll be dumping this distorted Na / alc / oil out onto the mounds and mounds of snow we have outside at time point tomorrow. If anything interesting happens I may toss a slice of Na on fresh snow and film it!

Well I will give you something for trying. +1 for the effort and your reports! :beer::beer:


Thanks for posting and sharing your experiment experience with us.
 
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Pretty cool, but isn't it (unusually) dangerous to do that on a flask with such a small opening? Can't the H2 build up and then ignite, blowing the flask up like a bomb?

Also I'm curious about the composition of the "fog". I also get it here and I'm incline to believe it's water vapor.
 
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The ratio of the diameter of the mouth of the flask to the volume of gas inside to the wall thickness is not such that there is sufficient explosion hazard as long as there is no obstruction to the mouth. If it were narrow mouth, thinner glass, or larger volume flask then it would be dangerous. At full H2 volume ignition just does a gentle pouf.

I think the fog is related to the burning sodium and not water vapor as it is only present when there is sodium ignition. Also the fog is acrid in nature and denser than air leading me to believe it is from NaOx and NaHx reacting with water vapor in the air.


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