A green powder is heated in a test tube. A gas is given off, and the powder becomes a black solid. In which classification of matter does the green powder belong?

1 Answer
Feb 8, 2016

My guess is that it is copper(II) carbonate.

Explanation:

Copper(II) carbonate is a green solid that decomposes on heating to give black copper(II) oxide and carbon dioxide gas:

#CuCO_(3(s))rarrCuO_((s))+CO_(2(g))#