Bedlasky
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Fun with barium orthoperiodate
Hi.
I synthesized some barium orthoperiodate Ba3(H2IO6)2. Synthesis is relatively easy, just dissolve some KIO4 in KOH to form K3H2IO6, barium salt is
precipitated by addition of BaCl2. Filtration took long time, vacuum filtration isn't possible because precipitate clog glass frit, so you must do
gravity filtration. I did some mistakes in calculations, because I thought that orthoperiodate have formula BaH3IO6 and later find out that it didn't,
so hopefuly my product isn't contaminated with metaperiodate (if it exist). My yield is 31,5 g (theory 28,73 g). So there are two options - my product
is contaminated with chloride (it shouldn't be, I did chloride test during washings) or it is hydrate. I'll do some analysis of the product later to
confirm its identity.
I did it mainly because I want to make some orthoperiodic acid, but I also wanted to try it as a flame colorant. It make MeOH flame green, not much
different from BaCl2. But in one case it make flame yellow, don't sure why. Maybe green colour was from BaI2???
I also tested its oxidizing capablities in the flame of alcohol burner. It's average oxidizing agent, reactions weren't as violent as I was expected.
You shouldn't underestimate it, but you don't need some special precautions. Do these experiments outside or in the fumehood because of barium
particles in the air, iodine vapor and other nasty stuff.
Reactions with sulfur and hydrazine sulfate weren't much spectacular, reaction with hydrazine sulfate give some iodine vapor (probably from
decomposition of periodic acid, HSO4- ion in hydrazine sulfate is pretty acidic). Reaction with sulfur give some yellow flames.
Very nice reaction was with MeOH. I add some barium periodate on to the combustion spoon and add little bit of MeOH. I put this mix in to the flame of
alcohol burner - it burned with nice sparkling yellow flame. I tried to replace MeOH with acetone, but this didn't produce such a nice flame (probably
because of burning carbon particles).
Another nice reaction was with tris. I again mixed tris and barium periodate on the combustion spoon and put it in to the flame. It burned with yellow
flame and on the combustion spoon grew pharao's serpent (in globural shape rather than snake shape).
Another reaction was with sulfamic acid. This produce lot of iodine vapor. When evolution of iodine stopped, dense white fume was produced instead. In
the first stage there are two reactions competing:
1) 12HSO3NH2 + Ba3(H2IO6)2 = BaI2 + 2BaSO4 + 10SO2 + 6N2 + 20H2O
2) 6HSO3NH2 + Ba3(H2IO6)2 = H5IO6 + Ba(SO3NH2)2
4H5IO6 = 2I2 + 7O2 + 10H2O
Second reaction is the major reaction, because large amount of iodine was released during this reaction. Also there was apparently unreacted sulfamic
acid, because of the dense white smoke in the second part of the reaction (which should be SO3).
I tried if addition of sulfamic acid to previously mentioned mixtures improve reactivity. And it did (not much, but still...). Ba periodate + HSO3NH2
+ S reacted more violently and give lots of iodine vapor. The same is true for Ba periodate + HSO3NH2 + N2H5HSO4. Addition of HSO3NH2 in to the
mixture of Ba periodate + tris apparently didn't improve reactivity (probably bacause tris neutralize sulfamic acid, so there wasn't formation of
orthoperiodic acid), but pharao's serpent on the spoon grew much larger than without sulfamic acid.
I didn't have any footage of these reactions, I didn't have much space in the fumehood for phone and I didn't want to put it too close to the alcohol
burner. Reactions with MeOH, tris and HSO3NH2 are really nice and I recommend these.
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j_sum1
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This all seems pretty cool.
Shame there are no pictures.
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Bedlasky
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I'll make some videos next week.
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Fery
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Nice experiment, looking forward video :-)
If the product is hard to filter, perhaps centrifugation could be done instead? When the product has low solubility in water, then also
recentrifugation with fresh water to get rid of last traces of chlorides?
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Bedlasky
International Hazard
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A don't have centrifuge, so that's not an option.
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Bedlasky
International Hazard
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Here are some videos I promised.
Barium periodate + MeOH - In the first video I remove mixture from flame after ignition, you can clearly see that barium periodate give yellow colour
to the methanol flame. In the second video I let mixture in the flame, boiling methanol make really big yellow flame.
https://youtu.be/NgM3XSzq9rE
https://youtu.be/O6Jubt0mz7g
Barium periodate + Fe
https://youtu.be/0WE2Zh53OdE
Barium periodate + Sb2S3 - this reaction is quite rapid, but not violent
https://youtu.be/iHDtN9psahc
Barium periodate + tris - this mixture produce really nice yellow flame, lots of carbon leftover on the combustion spoon.
https://youtu.be/kOP471VSHCY
Barium periodate + tris + HSO3NH2 - this mixture produce globural pharao's serpent
https://youtu.be/PS8Nkojk5uI
Barium periodate + HSO3NH2
https://youtu.be/iKh-Y61otz8
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