Thank you for your help!
The acidity or basicity of a compound is usually determined by examining the stability of the conjugate acid or base. Normally, atomic ions have very strong conjugate acids and bases, so they are so weakly acidic or basic that they produce neutral solutions. For example, HCl is a very strong acid, so its conjugate base, Cl-, is a very weak base. This is because HCl is acidic because it wants to get rid of the proton and would give it away to anything that comes its way. So Cl- would be a weak base because as soon as it takes a proton to form HCl, it would put back the proton producing Cl- immediately, thus making Cl- an ion that cannot accept a proton, therefore a very weak ion. base. This applies to most atomic ions you will encounter, such as Na+, K+, Ca2+, Mg2+, F-, Cl-, Br- and I-.
So for the first you would have CH3NH3+ and Cl-. Cl- is neutral, but the ammonium salt is the conjugate acid of methylamine, which is slightly basic. It would therefore be a weak acid and produce an acidic solution.
Sodium hypochlorite would dissolve into Na+ and OCl-. Sodium is again neutral, but OCl- is the conjugate base of hypochlorous acid, which is a weak acid. Therefore, it would result in a basic solution.
KCl would donate a potassium ion and a chloride ion, both neutral and produce a neutral solution.
Al(ClO4)3 dissolves in Al3+ and ClO4-. Al3+ is nearly neutral and ClO4- is the conjugate base of a weak acid. So that would be a basic solution.
CH3NH3Br is the same as the first, it’s acidic.
NaF would give sodium and fluoride ions, both neutral.
CaBr2 would give calcium and bromide ions, both neutral.
C6H5NH3NO2 is the most complicated of the group. Provides C6H5NH3+ and NO2- ions after dissociation. C6H5NH3+ is slightly acidic (same principle as CH3NH3+) and NO2- is the conjugate base of nitrous acid. Nitrous acid is very unstable and breaks down quickly. It would therefore form HNO2 by accepting a proton, so the solution would be slightly acidic.
gokay05tac is more correct. CaBr2 is neutral. But NaF is not. It’s basic.
Al(ClO4)3 is acidic and not basic.