Thermal decomposition is a chemical reaction in which a substance breaks down into simpler compounds or elements due to the application of heat.
Group 1 and 2 nitrates are thermally unstable compounds, meaning that they can easily decompose into their respective metal oxides, nitrogen dioxide gas, and oxygen gas when heated.
The general equation for the thermal decomposition of group 1 and 2 nitrates is: M(NO3)2 → MO + 2NO2 + 1/2O2, where M represents the metal ion.
The decomposition temperature of group 1 nitrates generally decreases down the group, while the decomposition temperature of group 2 nitrates generally increases down the group. This is due to the difference in the strength of the metal-oxygen bond.
Thermal decomposition of group 1 and 2 nitrates is commonly used in industrial processes, such as the production of metal oxides and fertilizers. It is also used in laboratory experiments to obtain pure metal oxides.