[vhpk]

Hi all,
I have a question about the bicarbonate salt of earth alkali metals. The textbook says that the compound of earth alkali bicarbonate can never be isolated in the solid. So is this related to the radius of the cation,i.e. the polarising power of the cations ( charge density) that causes the unstability for the compound ?
Thank you.

[BluRay]

It depends on which alkali earth metal. With Be it should be correct, with Mg I'm not totally sure, but I think it should exist; with the rest of the alkali earth metal it exists: just think of how Ca(HCO₃)₂ affect the water hardness and the rocks formation.

[vhpk]

Maybe you misunderstood my question, I don't mean that those compounds don't exist, I wanna know why they can't exist in an anhydrous form, i.e. from the solution to make the crystal solid.
Anw, thanks for your answer

[BluRay]

Maybe you misunderstood my question, I don't mean that those compounds don't exist, I wanna know why they can't exist in an anhydrous form, i.e. from the solution to make the crystal solid.
Anw, thanks for your answer

Ok.
I think the main reason is the fact the decomposition of bicarbonate gives a more stable chemical (the carbonate) and a gas (CO₂) which goes away and so shifts the equilibrium to the right:

Ca(HCO₃)₂  CaCO₃ + H₂O + CO₂