An unknown salt is either KBr, NH4Cl, KCN, or K2CO3. If a 0.100 M solution of the salt is neutral, what is the identity of the salt?

Answer 1

It must be KBr. Neither K^+ nor Br^- are hydrolyzed in aqueous solution.
NH4Cl gives an acid solution. (NH4^+) is hydrolyzed.
HCN gives a basic solution. CN^- is hydrolyzed.
K2CO3 gives a basic solution. CO3^2- is hydrolyzed.