What is copper carbonate made out of?

Answer 1

http://en.wikipedia.org/wiki/Copper(II)_carbonate

opper(II) carbonate (often called copper carbonateor cupric carbonate) is a blue-green compound (chemical formula CuCO3) forming part of the verdigris patina one sees on weathered brass, bronze, and copper. The colour can vary from bright blue to green, because there may be a mixture of both copper carbonate and basic copper carbonate in various stages of hydration. It was formerly much used as a pigment, and is still in use for artist's colours. It has also been used in some types of make-up, like lipstick, although it can also be toxic to humans. It also has been used for many years as an effective algaecide in farm ponds and in aquaculture operations. Copper carbonate was the first compound to be broken down into several separate elements (copper, carbon, and oxygen). It was broken down in 1794 by the French chemist Joseph Louis Proust (1754-1826).When burnt, it turns into a black powder. It can be used to bronze plate a metallic surface by adding suphuric acid and heat it then passing a charge through it with the meal in the liquid. Copper in moist air slowly acquires a dull green coating because its top layer has oxidised with the air. Some architechts use this material on rooftops for the interesting colour. The green material is a 1:1 mole mixture of Cu(OH)2 and CuCO3:[1] : 2Cu(s) + H2O(g) + CO2 + O2 → Cu(OH)2 + CuCO3(s) Copper carbonate decomposes at high temperatures, giving off carbon dioxide and leaving copper(II) oxide: : CuCO3(s) → CuO(s) + CO2(g) Basic copper(II) carbonate occurs naturally as malachite (CuCO3.Cu(OH)2) and azurite (Cu3(CO3)2(OH)2). # ^ Masterson, W. L., & Hurley, C. N. (2004). Chemistry: Principals and Reactions, 5th Ed. Thomson Learning, Inc. (p 498).