The bicarbonates of group 2 elements are stable only in solution.
Why is it so? Why do solid alkaline earth metal bicarbonates decompose/are unstable?
In other words, (thanks Zhe!), group 1 bicarbonates are stable. Group 2 bicarbonates are not. They decompose into the group 2 carbonate, water, and carbon dioxide. What is the principle difference between group 1 and group 2 bicarbonates that leads to a thermodynamic preference for the carbonate in one case and the bicarbonate in the other? Also, why is the preference only shown in the solid state, but not in the aqueous state?
I am not asking about thermal stability. I am just asking that what's the problem if we take these bicarbonates in solid state at room temperature and leave them there. Why would they decompose?