Ba(OH)2+NaHCO3====BaCO3(沉淀)+NaOH+H2O
nahco3+ba[oh]2=2naoh+bahco3
碳酸氢钠过量2NaHCO3＋ Ba(OH)2=Na2CO3 ＋BaCO3↓ ＋2H2O
