Eh so fast give up liao ah? Dun like that leh. Try lah.
Spoonfeeding u answers wun help u as much as giving u guidance on
ur own working attempts.
Comment on ur 1st qn : "Solubility" is a general term, that most
often refers to hydration, but in some cases involves hydrolysis.
CO2 actually undergoes limited hydration (ie. physical interaction
with water), not only because : the CO2 molecule only has the
capacity to accept but not donate hydrogen bonds ; although CO2 is
overall non-polar, its linear geometry allows for possible
permanent dipole - permanent dipole interactions with water; but in
addition also because it undergoes more extensive hydrolysis (ie.
chemical reaction with water) to generate the weak diprotic
carbonic(IV) acid, but whose position of equilibrium tends back
towards aqueous then gaseous CO2, due to thermodynamically
favorable positive entropy change. Overall, NH3 (which can both
accept and donate hydrogen bonds) is considered a lot more soluble
than CO2 (though most A level students and even JC teachers
oversimplify CO2 to be non-polar, and thus underconsider CO2's
capacity for hydration and hydrolysis as I've raised above).