KOH与H3PO4反应时,磷酸是三元酸逐步反应,反应的化学方程式分别是:
KOH + H3PO4 = KH2PO4 +H2O ,
KOH + KH2PO4 = K2HPO4 +H2O ,
KOH + K2HPO4 = K3PO4 +H2O