defective

........ yeah. what he said.

Richard probably knows beter than i do.

or you could try washing them with a solution of sodium carbonate and then with water (do it a few times).
i think that would probably do it.

if you already have crystals then most of the acid should be gone, keep washing them with water and keeping the water you used. after each wash test the water with blue litmus paper or universal indicator if you can find some. the water will be from a very pale yellow to red if its acidic and a light to medium green if neutral when using universal ind.

i think anyway, as far as my a level chemistry leads me to believe.

hope this helps.

fruitfulsteve, on May 16 2009, 12:09 PM, said:

I'm in the process of making some cuno3, i have got to the point where i have dark blue crystals but their still very acidic. I,m using conc nitric acid on copper wire (in a fume cupboard) and heating until brown smoke goes white. I was thinking of using cuco3 to neutralise!! any suggestions?

not too sure about that as copper carbonate is insoluble in water and only soluble in acidic solutions.

digger, on Apr 27 2009, 12:57 PM, said:

With the 3.5 on the motor the mill shaft will be 3.5/6 * 1425 = 831.25 rpm then the jar will be 1/7 * 831.25 = 118.75 rpm. Still a bit too fast I think.

So to get about 60rpm then go for a smaller pulley at 1.75".

There are obviously plenty of other size combinations that will work.

D

awsome, so i.e a bigger jar a little slower again?

top man.