Australia's Science Forum

Hi Guys
I've just been asked for zinc oxide for the prac where you heat it and it changes colour. I haven't got any. Does anyone know if there is a substitute I could use? for period 1 tomorrow.
thanks Krysia

try copper carbonate. goes from green to black and produces carbon dioxide in the process (so you can put a tube on the test tube and the other end in lime water and see it turn milky as well)

Thanks Rosalie
The teachers wants something that goes back to original colour after it is cooled. I think I'll give him some wax. Not quite as interesting I know but hey with a little more notice I could have got him some zinc oxide. A little more what............ notice, I've gotta be kidding.
Krysia

When Zinc Oxide is heated, it turns a pale, lemony color and when take off the heat, turns back to white. Nothing has happened to the zinc, it has not thermally decomposed.

We make up test tubes marked A = Zinc Oxide & B = Copper carbonate, The zinc oxide goes around and around again