Explain briefly why anhydrous copper(II) tetraoxosulphate(VI) is used to test for water​

Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon dioxide as shown below. caco3(s) cao(s) + co2(g) the kp for this reaction is 1.16 at 800°c. a 5.00 l vessel containing 10.0 g of caco3(s) was evacuated to remove the air, sealed, and then heated to 800°c. ignoring the volume occupied by the solid, what will be the mass of the solid in the vessel once equilibrium is reached?

Asolution is produced in which water is the solvent and there are four solutes. which of the solutes can dissolve better if the solution is heated?

Can anyone answer these questions? ? i need it before 1: 00pm today