Rank the following salts in order of increasing pH value of equimolar solutions: NaCN, KCl, NH4Cl.

Question

I'm not sure how to determine their pH just based off of their formula, could you please provide some information on how to solve other problems like these.

Answer 1

If it is a salt of a strong base and a weak acid, the pH of a solution will be > 7, i.e. basic. This is the case for NaCN, the salt of NaOH (strong base) and HCN (weak acid)

It if is a salt of a strong acid and a weak base, the pH of a solution will be < 7, .e. acidic. This is the case for NH4Cl, the salt of HCl (strong acid) and NH4OH (weak base)

If it is a salt of a strong acid and a strong base, the pH of a solution will be 7, i.e. neutral. This is the case for KCl, the salt of KOH (strong base) and HCl (strong acid)

Hope this helps.