Thermal decomposition
Calcium carbonate breaks down when heated strongly. This reaction is calledthermal decomposition. Here are the equations for the thermal decomposition of calcium carbonate:
calcium carbonate
calcium oxide + carbon dioxide
CaCO3
CaO + CO2
Other metal carbonates decompose in the same way, including:
- sodium carbonate
- magnesium carbonate
- copper carbonate
For example, here are the equations for the thermal decomposition of copper carbonate:
copper carbonate
copper oxide + carbon dioxide
CuCO3
CuO + CO2
Metals high up in the reactivity series (such as sodium, calcium and magnesium) have carbonates that need a lot of energy to decompose them. Indeed, not all the carbonates of group 1 metals decompose at the temperatures reached by a Bunsen burner.
Metals low down in the reactivity series, such as copper, have carbonates that areeasily decomposed. This is why copper carbonate is often used at school to show thermal decomposition. It is easily decomposed and its colour change, from green copper carbonate to black copper oxide, is easy to see.
.
Comments
No comments have yet been made