Except lithium carbonate, (LiCO3), the carbonates of all other alkali metals are stable towards heat, i.e., carbonates of alkali metals (except LiCO3) do not decompose on heating. LiCO3 decomposes on heating to give lithium oxide (LiCO3).
The carbonates of alkaline earth metals are relatively less stable. On heating, they decompose to give corresponding oxide and CO2 gas. The decomposition temperature for alkaline earth metal carbonates increases as we go down the group.
