11SCI
types of reactions
C. Decomposition 1
To decompose means to break something into simpler parts. In chemistry this
could mean breaking a compound into its elements or into simpler compounds.
Decomposition reactions involve heat (thermal decomposition) or catalysts
(catalytic decomposition).
For this internal, you only need to learn about the decomposition of carbonates and
hydrogen carbonates.
Metal carbonates decompose to form a metal oxide and carbon dioxide.
eg
CaCO3
heat
CaO
+
CO2
Write word and balanced chemical equations for the decomposition of the following metal
carbonates:
1. Sodium carbonate
Na2CO3
Sodium oxide +
heat
2. Copper carbonate
CuCO3
heat
heat
heat
5. Magnesium carbonate
MgCO3
CuO
CO2
Carbon dioxide
+
CO2
+
Carbon dioxide
ZnO
+
CO2
Lead oxide
+
Carbon dioxide
PbO
+
CO2
Zinc oxide
4. Lead carbonate
PbCO3
+
Copper oxide +
3. Zinc carbonate
ZnCO3
Na2O
Carbon dioxide
Magnesium oxide + Carbon dioxide
heat
MgO
+
CO2