Search found 199 matches
- 23 Feb 2023, 11:46
- Forum: Chemistry and Labware - General
- Topic: standardized NaOH
- Replies: 20
- Views: 12204
Re: standardized NaOH
Taken from Google. It's not about the concentration, it's about the properties of the solid chemical. Standards are used in analytical chemistry. Here, a primary standard is typically a reagent which can be weighed easily, and which is so pure that its weight is truly representative of the number of...
- 23 Feb 2023, 08:21
- Forum: Safety with Chemicals
- Topic: Environmental friendly Disposable Gloves?
- Replies: 20
- Views: 8727
Re: Environmental friendly Disposable Gloves?
Oh I feel you pain! We have some polyethylene gloves that were recyclable when REDcycle was functioning (if they were cleaned and dried), but I know of no environmentally friendly option at the moment. I actively discourage unnecessary glove use. We all need to talk to our suppliers and get them thi...
- 23 Feb 2023, 06:58
- Forum: Chemistry and Labware - General
- Topic: Sodium Dichromate for cleaning glassware
- Replies: 23
- Views: 13177
Re: Sodium Dichromate for cleaning glassware
I use 36% HCl on glassware. Obviously, I use the fume cupboard and PPE. Leave to soak overnight and voila! Usually gets anything off. I return the HCl to a stock bottle for for future use - it lasts for ages.
- 14 Feb 2023, 09:01
- Forum: Sourcing Materials & Eq Repairs
- Topic: Volumetric flasks
- Replies: 10
- Views: 7046
Re: Volumetric flasks
Taken from Google - Class A Borosilicate volumetric glassware has superior thermal and chemical resistance and is better suited to glassware for storage of solutions, e.g. flasks. The use of Class A borosilicate glass for volumetric glassware means accuracy is retained over a longer working lifetime...
- 14 Feb 2023, 08:49
- Forum: Safety with Chemicals
- Topic: storage of H2O2
- Replies: 12
- Views: 11526
Re: storage of H2O2
We use H2O2 a lot, and I always buy the 2.5L container. We keep it in the fridge (technically not recommended unless it's a "spark-free" fridge, whatever that is). Have had no issues with decomposition yet. I would estimate sometimes we use stuff that's at least two years old.
- 24 Nov 2022, 06:56
- Forum: Chemistry and Labware - General
- Topic: Chemical store Room
- Replies: 21
- Views: 13068
Re: Chemical store Room
Our ferrous chloride is in CS cabinet with the other class 8 stuff.
- 24 Nov 2022, 06:50
- Forum: Miscellaneous
- Topic: looking for slater bugs-investigating science
- Replies: 2
- Views: 4215
Re: looking for slater bugs-investigating science
Slaters are very common and easy to find. Leaf litter or under logs or rocks are the best places. Good luck!
- 22 Nov 2022, 12:09
- Forum: Safety with Chemicals
- Topic: Experiment gone wrong
- Replies: 28
- Views: 10678
Re: Experiment gone wrong
The versions I've seen call for lighter fluid, metho, or ethanol. Perhaps any accelerant will do.
- 22 Nov 2022, 08:32
- Forum: Safety with Chemicals
- Topic: Experiment gone wrong
- Replies: 28
- Views: 10678
Re: Experiment gone wrong
I just got sent a link via RiskAssess from a teacher who wants to show the kids the experiment that went so wrong. The first thing my eye fell on was "Do not perform this experiment in windy conditions". This warning was repeated several times. I think that teacher is in big trouble.
- 22 Nov 2022, 07:48
- Forum: Safety with Chemicals
- Topic: Experiment gone wrong
- Replies: 28
- Views: 10678
Re: Experiment gone wrong
And sugar. We've done it here small-scale. Fine to do inside. I wonder why they decided on outdoors. Teacher must have used a lot of metho. It would have been like napalm - those kids are not going to enjoy science with flames or explosions in the future. I wonder if anyone did a risk assessment. Su...
- 09 Nov 2022, 08:04
- Forum: Chemistry and Labware - General
- Topic: pH Charts
- Replies: 25
- Views: 9642
Re: pH Charts
And thank you from me too!
- 01 Nov 2022, 07:59
- Forum: Chemistry and Labware - General
- Topic: pH Charts
- Replies: 25
- Views: 9642
Re: pH Charts
These are amazing. Will definitely be appropriating them. Thank you.
- 27 Oct 2022, 12:15
- Forum: Safety with Chemicals
- Topic: waste bottle labels
- Replies: 18
- Views: 9213
Re: waste bottle labels
For an example, this is from RiskAssess for sodium nitrate.
Disposal
Retain for collection by a waste service. Do not place in the garbage. <100 g/day may be dissolved in 10 times the mass of water and poured down the drain.
If you don't have RiskAssess, use the SDSs.
Disposal
Retain for collection by a waste service. Do not place in the garbage. <100 g/day may be dissolved in 10 times the mass of water and poured down the drain.
If you don't have RiskAssess, use the SDSs.
- 25 Oct 2022, 08:12
- Forum: Chemistry and Labware - General
- Topic: Electrophoresis Kits
- Replies: 21
- Views: 13965
Re: Electrophoresis Kits
I am amazed! And now feeling slightly inadequate.
- 18 Oct 2022, 11:26
- Forum: Sourcing Materials & Eq Repairs
- Topic: swan neck tubes
- Replies: 25
- Views: 12928
Re: Swan neck tubes
Perhaps try "swan-neck flask" instead.
- 18 Oct 2022, 09:23
- Forum: Recipes and Pracs
- Topic: Calcium Fluoride
- Replies: 5
- Views: 4969
Re: Calcium Fluoride
I made up a 0.1M solution of calcium fluoride last week and got a cloudy solution with some left on the bottom, so some of it dissolved. Interestingly, CaF2 is so insoluble that the labelling program on RiskAssess won't allow for the concentration to be listed - it assumes you're labelling the solid.
- 13 Oct 2022, 11:34
- Forum: Safety with Chemicals
- Topic: waste bottle labels
- Replies: 18
- Views: 9213
Re: waste labels
I just use paper labels and write in pencil on those. I do put stickers on the bottles re who can use them (the coloured dots). All the heavy metals should be separate, as they're too hard to neutralise when mixed. I learned from somewhere... Lead waste - add solid sodium carbonate, decant clear sup...
- 13 Oct 2022, 11:03
- Forum: Recipes and Pracs
- Topic: Iron III Nitrate
- Replies: 7
- Views: 5134
Re: Iron III Nitrate
I'll know this by next week! We're doing that prac too. Sorry I can't help you now.
- 08 Sep 2022, 13:07
- Forum: Announcements
- Topic: Banned from 1 NOV
- Replies: 43
- Views: 16550
Re: Banned from 1 NOV
I love it that we are finally doing this.
- 08 Sep 2022, 12:51
- Forum: Biology, Physics...
- Topic: waste from dissections
- Replies: 9
- Views: 5601
Re: waste from dissections
Already have. They accept any organic matter.