(3)盐+碱—新盐+新碱 CuSO4+ 2NaOH= Cu(OH2\+ na2SO4 Na,CO3+ Ca(OH)2=CaCO3+ 2NaOh (4)盐+盐—新盐+新盐 NaCl+AgNO3=AgCI\+NaNO3 Ba(No3)2+Na2S04=BaSO4 +2NaNO3(3)盐+碱——新盐+新碱 CuSO4 + 2NaOH＝Cu(OH)2↓ + Na2SO4 Na2CO3 + Ca(OH)2＝CaCO3 ↓+ 2NaOH (4)盐+盐——新盐+新盐 NaCl + AgNO3＝AgCl ↓+ NaNO3 Ba(NO3 )2 + Na2SO4＝BaSO4 ↓ + 2NaNO3