Cleaning evaporating dishes

[agregory]

We have some evaporating dishes which have been used for an Evaporating Coca Cola Prac. The dishes have had the Coke burned onto them terrible and nothing will get it off (scrubbing, bleach, HCl).

Any help?

[smiley]

Try soaking them in a fairly strong Napisan solution. Leave them overnight at least, or even longer. Works on ceramics at home too!

[dime]

If you don't have napisan, you can use sodium hydroxide about 2M. Leave to soak for a couple of days, and the black coke comes off completely.

[ana.santos]

I had the same problem with burning magneium in crucibles. Tried soaking in nitric acid and scrubbed with steel scrubber but some still have some marks on them.

Ana

[agregory]

Thanks!

[Krysia Lee]

Something I got from this site was to put a liitle rice, sand and water in the bottom of the evaporating basin with a magnetic stirrer and let it go till clean. Works a treat.