Australia's Science Forum

Just wondering how common this is .
I had a few Sodium Hydroxide Dropper bottles that have lately started to crack .
At first , I noticed that the labels were going crusty with white NaOH coating them . When I soaked off the labels , I noticed that there were cracks that had developed . Some had one , some had several .

Now these bottles have been reused for NaOH for probably well over 20-30 years . Every so often they get a clean out to remove the build-up that forms .
These ones have not been cleaned for a about 3 years when they were relabels for GHS . You can see the cracks .

hi
Storage/Stability
Sodium hydroxide stock solutions should be stored in plastic containers. Glass containers should be completely avoided in the preparation and storage of sodium hydroxide solutions.
NaOH will dissolve glass and form silicon hydroxide. The only thing that NaOH should be stored in are containers made of HDPE (high density poly-ethylene). Other plastics will work if they are airtight and chemically compatible, but to be safe please stick with HDPE.

Excellent Super Bug, what was the Molar you had in them?

Ahhh thankyou Super Bug . I didn't know that . I figured that since they had been stored that way for so long , it was OK . Did wonder what the crud was that forms in them though .
BTW, it was 1mol/L Labbie .
Personally I would prefer to store them empty and fill on request , but those that don't plan or like to do things on the fly prefer them ready to grab .

Or use the plastic dropper bottles?

we use these from science supply

I've suggested those to my HT but our kids are rather special .To many Bushfires , floods and Covid has rattled their brains .
She thinks there is a high likelihood of Sodium Hydroxide getting squirted at each other .It's a no from her.

We have been using stull bottles for over 10 years and have never had a incident, the first original ones there was a problem with the lids splitting but thats been fixed and nolonger a problem. Where Glass dropper bottles were being knocked over, spilled or smashed and contaminated, swapping droppers.

Will never go back, love them

bigmack wrote: ↑20 Jun 2022, 10:18 I've suggested those to my HT but our kids are rather special .To many Bushfires , floods and Covid has rattled their brains .
She thinks there is a high likelihood of Sodium Hydroxide getting squirted at each other .It's a no from her.

Having a bit of the same problem here. On top of the impacts of all these traumas, lockdowns have sealed the deal. Students came back this year very unsettled. Year 7 were all over the shop but the last normal year for them was when they were in Year 4. That year was finished off with the world being on fire. I think students are just starting to settle down a bit but not what we would normally expect.

I don't think I could trust a lot of our classes at the moment with squirty bottles!

I can relate to that Merilyn1 & Bigmack,