Cost of chemicals, purchasing and shelf life

Cost of chemicals, purchasing and shelf life

Author
Discussion

airbrakes

Original Poster:

10,404 posts

161 months

Tuesday 17th December 2013
quotequote all
Afternoon all,

I was considering making some "mirror bottles" as unusual present for people in the future, using the standard methods of an aldehyde + tollens reagent to get a silver deposit. Obviously, as Tollens goes off very quickly then it had to be made fresh in the bottle from stock ingredients, and here we run into a problem. It seems the constituent stuff is only available in industrial lab quantities at huge prices - on the very rare occasion a price is listed rather than just a COSHH sheet with no indications on how to order. Very little seems to be stated of the shelf life o the chemicals involved too, does this mean they are ok to leave for a long time?
I then again ran into a similar situation looking for some pure acetone to make up a penetrating oil mixture.

Can anyone help with recommendations of where to buy small quantities?

thanks,


matt

8Ace

2,696 posts

199 months

Wednesday 18th December 2013
quotequote all
Sigma Aldrich:

http://www.sigmaaldrich.com/chemistry.html

They sell smaller quantities of loads of things to be used in research. I'm not sure they sell to the public though, but worth a try.

Alternatively befriend an organic chemist (preferably doing a PhD) as they have access to pretty much anything in their labs.

mrmr96

13,736 posts

205 months

Wednesday 18th December 2013
quotequote all
ebay?

Hairbrakes

Original Poster:

10,404 posts

161 months

Friday 20th December 2013
quotequote all
Thanks for then suggestions! I'll check out the Sigma Aldrich site

Tanguero

4,535 posts

202 months

Friday 20th December 2013
quotequote all
Silver nitrate, sodium hydroxide and ammonia - none of them have a short shelf life and at least two of them are available over the counter from Robert Dyas... wink

moreflaps

746 posts

156 months

Sunday 22nd December 2013
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This contains several alternative methods....
http://www.jstor.org/stable/40710170

HTH

Cheers

Simpo Two

85,599 posts

266 months

Sunday 22nd December 2013
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Amused that the thread starts with 'airbakes' and ends with 'moreflaps'!

Is there anyone called 'cabindoorstomanual'?

Hairbrakes

Original Poster:

10,404 posts

161 months

Sunday 22nd December 2013
quotequote all
rofl

thatdude

2,655 posts

128 months

Thursday 2nd January 2014
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Some chemicals will readily absorb moisture out of the atmosphere (for example, sodium hydroxide). Might be worth riging up some sort of dessicated container (in labs, we have a glass container with dessicant at the bottom, and the metal grill over it on which to put the chemicals. The container can be purged with nitrogen or kept under vacumn too but that's probably extreme)

Organic compounds may oxidise over time. Some may form peroxides too.

19Dogger87

68 posts

140 months

Thursday 2nd January 2014
quotequote all
www.nels.co.uk also sell small quantities usually next day delivery too