A piece of malachite is heated in a glass pipette closed by a rubber hat. A tissue paper wetted with methylated spirit is fixed in the pipette head. A tube connects the other end of the pipette
with lime water in a vial.
Colour changes from green to black.,
Water drops at the cool parts of the pipette. Gas bubbles make lime water milky.
Ethanol vapour changes the black colour to the colour of copper.
Explanation of heating
Malachite is transformed into CuO + water + CO2
Explanation reaction with methylated spirit
CuO is transformed into Cu + water + CO2.
First publication: 1999 Last modification: 22.12.2013