UnintentionalChaos
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Storage of Conc. NaOH
I know that NaOH (especially when boiling hot or molten) can dissolve glass at a very appreciable rate. How does glass fare against highly
concentrated room temperature solution (10M) in the long run? I was wondering if you get a sodium silicate barrier that does not dissolve further
(similar to the storage of conc. H2SO4 in metal canisters wheras dilute solution would liquefy them in a hurry). The reason I ask is that I went very
out of my way to make a standardized solution today (using all the good analytical lab procedures that I never bother with) and am currently storing
it in brown glass. I probably will not use this solution much and do not need it to eat holes in the container and spill everywhere after a few
months, though it is quite thick and probably would not "spill" so much as ooze. 
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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The_Davster
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You need an appropriate plastic bottle. Look up some resistance charts.
I have 500mL of 1M stuff forever sealed in ground glass pennyhead stoppered bottles. Need to do something with those at some point...
Also some 50mLs of 50% stuff that has really thickened as a result of storage in a small glass bottle. It is useless as a reagent now, so I am just
seeing how much it affects the glass. So far the glass does seem a bit thinner, and the NaOH solution is as thick as warm honey.
[Edited on 8-4-2007 by The_Davster]
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UnintentionalChaos
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Warm honey?! Quite a scary thought. Mine might look like honey too since it's
in brown glass.
Anyway, I've swapped out to a heavy walled Nalgene brand HDPE bottle and watered the stuff down to 4M since that should also slow chemical attack.
Right now, that's the best I have and from what I can find, looks like it will hold up for a while.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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16MillionEyes
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Yes, as Davster pointed out. Why don't you try storing it in a resistant plastic bottle. Try cola bottles and see if they work  .
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not_important
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HDPE is good, polyolefins are effectively mineral wax - long chain hydrocarbons, not much for alkali to get a grab onto.
Soft drink and juice bottles are PET, an ester; like monomeric esters strong base will hydrolyse it.
ref on resistence of some plastics
http://simport.sogetel.net/en/charts.php
The only real problem with polyolefins is that carbon dioxide will slowly diffuse through them and react with the hydroxide. The rate is affected by
the thickness of the plastic, and usually isn't a significant problem.
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chemrox
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Is there really a problem with 1N or 2N NaOH in glass? I would think the 50% might yield sodium silicates of various compositions but not 2N ...where
can I read some hard data on this?
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woelen
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I once stored sodium hydroxide (10% or so) in glass bottles, but in the course of a few weeks already the glass was attacked a little (it was matte,
somewhat milky). Simply do not store NaOH in glass bottles, even fairly dilute material attacks the glass. The glass will not break within a few
weeks, but the NaOH will be spoilt and not be suitable for experiments anymore.
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not_important
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I can't find the reference, but I remember that glass not be used for storing hydroxide stronger than 2N.
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solo
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Catalog Number: 153495, 199465, 1688145
Sodium hydroxide
Structure:
Molecular Formula: NaOH
Molecular Weight: 40.0
CAS # 1310-73-2
Synonyms: Caustic soda-beads; Soda lye; Sodium hydrate
Physical Description: White powder or clear, colorless solution
Solubility: 1g dissolves in 0.9 ml water; 0.3 ml boiling water, 7.2 ml absolute alcohol, 4.2 ml methanol; insoluble in glycerol. The dissolution of
sodium hydroxide in water is a highly exothermic reaction. Sodium hydroxide stock solutions should be stored in plastic containers. Glass containers
should be avoided in the preparation and storage of sodium hydroxide solutions because it will etch the glass (typically anything over 2 N will etch
glass). Keep solutions protected from air as much as possible since contact with air will form sodium carbonate.1
Description: A caustic reagent which is typically used to neutralize acids and prepare sodium salts of reagents.1 Sodium hydroxide is a common reagent
for the adjustment of pH in buffers. It is also used in production of pulp and paper, soaps and detergents.
Sodium hydroxide is also used in:
o The Maxam-Gilbert DNA sequencing technique.2,5
o An RNA gel blot procedure for simultaneous transfer and fixing of RNA to a positively charged nylon membrane.4
o The decontamination of mycobacterial isolates.3
..............source,
http://www.mpbio.com/product_info.php?cPath=491_6_41&pro...
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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