awlb2
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Sodium Hydroxide
If anyone is able to help me with a question I have I would be very grateful. I have a dilute solution (approx. 3moldm/3) of NaOH in water, I would
like to know if the water could be evaporated without significant losses as Na2CO3? For example if a small amount (E.g. a single
drop) was left for some time(at room temp.), until all water evaporates would it still contain significant amounts of NaOH. What if the solution was
boiled to dryness?
Many thanks in advance!
[Edited on 29-12-2016 by awlb2]
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brubei
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Sodium hydroxyde exposed to atmospheric CO2 slowly gives hydrogenocarbonate :
NaOH + CO2 <<<=> NaHCO3
This result in a light loss of basicity strenght but the équilibrium is reversible and your NaOH is recovered as you will evaporate it to dryness.
[Edited on 29-12-2016 by brubei]
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macckone
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Sodium hydroxide will not go to dryness without heat.
Almost 10% is converted to carbonate in commercial operation.
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unionised
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Quote: Originally posted by brubei  | Sodium hydroxyde exposed to atmospheric CO2 slowly gives hydrogenocarbonate :
NaOH + CO2 <<<=> NaHCO3
This result in a light loss of basicity strenght but the équilibrium is reversible and your NaOH is recovered as you will evaporate it to dryness.
[Edited on 29-12-2016 by brubei] |
MAinly wrong.
The product of leaving NaOH exposed to air is initially the carbonate and eventually (so I'm told; I never waited that long) the sesquicarbonate.
Boiling down a solution to dryness will not give you NaOH.
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awlb2
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Thanks everybody, my NaOH is still useful as a solution nonetheless.
Happy New Year Everyone!
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AJKOER
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Heat while connected to an even bad working vacuum pump to your NaOH/H2O solution.
It should boil faster absent the presence of CO2 and air.
Not commercial path due to cost.
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