Sodium Hydroxide solution

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mtg
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Sodium Hydroxide solution

Post by mtg »

My sodium hydroxide has liquefied and I was wondering how to make up a rough solution for junior chemistry. 1M ish
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Labbie
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Re: Sodium Hydroxide solution

Post by Labbie »

Can you dilute down perhaps... :wub: :redcard: We use to have silca gel the packets you get with your shoes and things. Cling wrap on top of the chemical with a silca gel pack on top of the glad wrap. screw the lid down and turn the cling wrap up over the lid. Seemed to keep a little longer, that is with the solid sorry. :wub: :cry2:
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Merilyn1
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Re: Sodium Hydroxide solution

Post by Merilyn1 »

My advice: send it off for disposal and buy fresh. Solid NaOH is not expensive. You will have no way of knowing the strength, even for juniors.
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Labbie
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Re: Sodium Hydroxide solution

Post by Labbie »

Yes but perhaps you can dilute a 2m down for 1m .
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Merilyn1
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Re: Sodium Hydroxide solution

Post by Merilyn1 »

Labbie wrote: 16 Mar 2021, 14:45 Yes but perhaps you can dilute a 2m down for 1m .
Did I misread? I got the idea that the solid had liquified. I think you're idea of sealing it with the silica sachet would be a great idea to prevent, but even ensuring the lid is on tightly can help (depends where you are in terms of humidity).
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MissKat
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Re: Sodium Hydroxide solution

Post by MissKat »

If you really want to, could make a dilute solution of known volume and titrate it against a primary standard. But as Merilyn mentioned, much easier to buy a new bottle :)
bigmack
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Re: Sodium Hydroxide solution

Post by bigmack »

You can buy a jar of caustic soda from the supermarket . On the label it says "cleans drains faster" ....just say'n 8)
mtg
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Re: Sodium Hydroxide solution

Post by mtg »

It's a liquid now. Which is unusual for this as we use so much. I think covid lock down might be the cause. All those common chems left unused for a year. Can't afford the delivery for 1 jar and I can use it for cleaning as it doesn't need to be collected as chem waste. I will probably use it for pH columns then. We used to make "bucket strength" which was an unknown strength but very dilute, common chemical that juniors used stacks of that didn't need to be analytical, but auditors don't like that. LOL And thanks for the idea of silica sachet. I will also check out drain cleaner some of which have other stuff in them I've noticed.
bigmack
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Re: Sodium Hydroxide solution

Post by bigmack »

mtg wrote: 17 Mar 2021, 10:37 I will also check out drain cleaner some of which have other stuff in them I've noticed.
Sorry I may have been a bit cryptic. I was suggesting you can just tip it down the drain ( with the tap running ) rather than pay for waste disposal of it.

We just use Plain Caustic Soda from the Supermarket here .It is just Sodium Hydroxide .
Not sure about Draino or CLR, I think they have other crap in them .
bigmack
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Re: Sodium Hydroxide solution

Post by bigmack »

Labbie wrote: 18 Mar 2021, 15:11 Or add Sodium Carbonate to (bi-carb soda) to neutralise it before it goes down the sink. So much cheaper.
How so Labbie , I would have thought you'd need to add quite a bit of acid to it ....not more base
bigmack
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Re: Sodium Hydroxide solution

Post by bigmack »

Labbie wrote: 19 Mar 2021, 09:35 I would'nt put any acid down the sink with out neutralising it first.
Me nether, but Sodium Hydroxide isn't an acid.
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