(1)甲为Na2CO3,乙为Na2SO4,丙为NaCl,丁为NaNO3;
(2)甲:Na2CO3+BaCl2==BaCO3↓+2NaCl,乙:Na2SO4+BaCl2==BaSO4↓+2NaCl;
(3)NaCl+AgAgNO3==AgCl↓+NaNO3
(1)甲为Na2CO3,乙为Na2SO4,丙为NaCl,丁为NaNO3;
(2)甲:Na2CO3+BaCl2==BaCO3↓+2NaCl,乙:Na2SO4+BaCl2==BaSO4↓+2NaCl;
(3)NaCl+AgAgNO3==AgCl↓+NaNO3