Potassium carbonate cannot be prepared by Solvay process. Why?

Account for the following: Potassium carbonate cannot be prepared by Solvay's process.

Alkali metals are highly reactive due to their low ionization enthalpies. How is sodium carbonate prepared using Solvay process? Is this method suitable for the preparation of potassium carbonate? Justify

Standard solution of sodium hydroxide cannot be prepared by weighing, why?

Reaction by which benzaldehyde cannot be prepared is

Potassium permanganate KMnO_(4) is not a primary standard Why?

CO_2 cannot be liquified above 31.1°C. Why?

Copper cannot liberate (H)_(2). from acids. Why?