Predict whether these $1.0~\mathrm{M}$ solutions are acidic, basic, or neutral. Lets start with $\ce{CH3NH3+NO3-}$

How do I approach a problem such as this?

I certainly do not know all the chemical compounds that exist thus what is my method?

I am guessing that $\ce{NO3-}$ does not hydrolyze and $\ce{CH3NH3+}$ does.

Thus, $\ce{CH3NH3+ + H2O -> CH3NH2 + H3O}$ = ACID

(b) $\ce{NaI~(aq)}$

$\ce{Na}$ does not hydrolyze and neither does iodine, but why?

(c) $\ce{NaNO2}$

$\ce{Na}$ again does not hydrolyze but from the first example neither does $\ce{NO2}$

Does this have something to do with either the solutions have a hydrogen atom or $\ce{OH-}$ molecule?