Answer
See answer below.
Work Step by Step
a) $2\ CH_3CO_2H(aq)+Mg(OH)_2(s)\rightarrow 2\ H_2O(l)+Mg^{2+}(aq)+2\ CH_3CO_2^-(aq)$
From left to right:
Acetic acid, magnesium hydroxide, water, magnesium acetate (soluble, so it's in ionic form)
b) $HClO_4(aq)+NH_3(aq)\rightarrow NH_4^+(aq)+ClO_4^-(aq)$
From left to right:
Perchloric acid, ammonia, water, ammonium perchlorate (soluble, so it's in ionic form)
