少量Ba(OH)22 NaHSO4 + Ba(OH)2 = BaSO4↓+ 2 H2O + Na2SO42 H+ +SO42- + Ba2+ + 2 OH- = 2 H2O + BaSO4↓过量Ba(OH)2NaHSO4 + Ba(OH)2 = BaSO4 ↓+ NaOH + H2O H+ + SO42- + Ba2+ + OH- = BaSO4↓ + H2O