Answer
See answer below
Work Step by Step
a) $H_3PO_4(aq)+3\ KOH(aq) \rightarrow K_3PO_4(aq)+3\ H_2O(l)$
Reactants: Phosphoric acid, potassium hydroxide
Products: Potassium phosphate, water
b)$H_2C_2O_4(aq)+Ca(OH)_2(aq) \rightarrow CaC_2O_4(aq)+2\ H_2O(l)$
Reactants: Oxalic acid, calcium hydroxide
Products: Calcium oxalate, water