Re: What The Fuck?
Break the ammonium nitrate into the associated acid and base used to form the salt.
NH4NO3 (aq.) --> NH4+ (aq.) + NO3- (aq.)
In water NH4+ behaves as an acid (easy to lose proton due to positive charge) and NO3- behaves as a base (easy to gain proton due to attractive negative charge), so:
NH4+ (aq.) + OH- (aq.) --> NH3 (aq.) + H2O (l)
NO3- (aq.) + H3O+ (aq.) --> HNO3 (aq.) + H2O (l)
Now HNO3 is a strong acid and NH3 is a weak base, so their conjugate bases and acids make up the salt NO3- + NH4+.
So NO3- is a weak conjugate base (as HNO3 is a strong acid) and NH4+ is a strong acid (as NH3 is a weak base), hence the salt is acidic.