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qustion about sodium


langstonwf2
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if you place sodium in a container of water you will have a solution of sodium hydroxide right? and if you boil the water out will you have pure sodium hydroxide or will it evaporate along with the water?

 

 

also could you make small amounts of sodium from molten sodium hydroxide with out an inert atmosphere (small like a few milligrams small)

 

does anyone have a link of what molten sodium hydroxide looks like?

 

http://www.sas.org/E-Bulletin/2001-10-05/chem/column.html This website makes making sodium seem easy is it really that simple?

 

-thanks

Edited by langstonwf2
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You will be able to reduce it down to a white solid. Just to check (I'm sure you know this but just to be safe) the initial reaction is very violent! i.e. it explodes with enough sodium! It is (or was) a standard demonstration in schools as to the reaction of groupI metals with water.

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DrP is right, it is a voilent reaction. but as per your suggestion it is true that sodium hydroxide is obtained. well to be exact, sodium hydroxide 'crackles' when you heat it and I actaully have never heard about the molten sodium hydroxide. Try Wikipedia, it might help!

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Yeah, sodium hydroxide is a CO2 magnet. It is why you don't prepare standard solutions of NaOH using old bottles of solid NaOH, or you don't make standard solutions ahead of time if the concentration is critical. All of the alkali hydroxides do a good job of removing CO2 from the air. I believe that most chemical CO2 scrubbers are KOH or NaOH.

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It is. :cool:

 

Maybe in Rio - not sure if we can still do it here in the UK. I'm only going by what someone told me so I could be wrong, but I think the health and safety crowd put a stop to it. How can we check this out?

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Maybe in Rio - not sure if we can still do it here in the UK. I'm only going by what someone told me so I could be wrong, but I think the health and safety crowd put a stop to it. How can we check this out?

 

 

Of course the demonstration Na + H2O is made by experienced teachers and inside a fume hood in Chemistry Technician schools (or college, I don't know how are Technician Schools named over there).

And those demonstrations usually come with phenolphthalein to prove the existence of Sodium Hidroxide.

I don't think it's dangerous since used the sodium is used in low quantity.

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Of course the demonstration Na + H2O is made by experienced teachers and inside a fume hood in Chemistry Technician schools (or college, I don't know how are Technician Schools named over there).

And those demonstrations usually come with phenolphthalein to prove the existence of Sodium Hidroxide.

I don't think it's dangerous since used the sodium is used in low quantity.

 

nevertheless, in some places it has caused accidents and has been banned in schools

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that video has been proven to be a hoax. It turned out they had explosives to cause the explosions, and caesium was not involved at all.

 

Actually, there is a website somewhere with videos of five grams of caesium and five grams of rubidium being dumped into water, and surprisingly they're not as violent as you'd imagine. This is explained by the fact that 5 g of cesium contains less moles of atoms than five grams of sodium or potassium, since each atom weighs so much more.

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that video has been proven to be a hoax. It turned out they had explosives to cause the explosions, and caesium was not involved at all.

 

Actually, there is a website somewhere with videos of five grams of caesium and five grams of rubidium being dumped into water, and surprisingly they're not as violent as you'd imagine. This is explained by the fact that 5 g of cesium contains less moles of atoms than five grams of sodium or potassium, since each atom weighs so much more.

 

I was suspecting... It was very sensacionalist.

 

Well, i've never thought by this point of view... the explanation based on quantity of matter in this case was very interesting, as everyone thinks the same weight of cesium would make a enormous explosion.

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For critical drying and CO2 removal, eg. for conditioning GC carrier gas, etc. we usually use a layercake of LiOH and molecular sieves.

 

YT is correct, the carbonate is a problem even in very fresh mixtures and a small peak can always be seen when using it to match eluent with anion exclusion chromatography. This is a plus, however, when you want to know the precise carbonate content so that you can correct titrant concentration.

 

Another fine demonstration if to melt some lithium in a glass container over sand. Nice!

 

Terms like "risk management" and "ambulance chasing lawyer" have largely ruined the fine art of scientific demonstrations. Collapsing cans, colored fire and small explosions tend to gain attention a bit more readily than "computer simulations". Pity.

 

 

Cheers,

 

O3

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Our teacher did the Sodium and water reaction. But he used a really really small amount so it did pretty much nothing. But we watched a video where two guys in lab coats through different group one metals into a pound and watched them explode.

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Yeah. Because Rb and Cs are denser than water, if you get a shallow enough vessel the gas formation and heat can cause a rapid expansion of gas leading to the explosion. In addition, a relatively thin (compared to the ceramic substance of a bathtub) glass container will do a fine job of breaking.

 

I think to get the damage shown in the Brainiac skit in a bathtub you'd need a prohibitively expensive sample of Rb or Cs.

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