... 2-C 3-D 4- D 5-A 6-D 7-B 8-C 9-D 10-B 11-A 12-D 13-A 1 4- C 15-D 16-A 17-C 18-D 19-C 20-B 21-C 22-C 23-B 2 4- C 25-C 26-B 27-A 28-C 29-A 30-D 31-C 32-B 33-A 3 4- B 35-B 36-D 37-C 38-C 39-A 40 -B LỜI GIẢI... BTKL: mX + mH2SO4 = mY + mZ + mH2O => mH2O = 38,36 + 0,87.98 – 111 ,46 – 1,9 = 10,26 (g) => nH2O = 0,57 (mol) BTNT H => nNH4+ = (2nH2SO4 – 2nH2 – 2nH2O ) /4 = (2.0,87 – 2.0,2 – 0,57) /4 = 0,05 (mol)... Fe3O4 + 4H2SO4 → FeSO4 + Fe2(SO4)3 + 4H2O => thu muối a → 4a (mol) c) 2CO2 dư + Ca(OH)2 → Ca(HCO3)2 => thu muối d) Cu + Fe2(SO4)3 dư → CuSO4 + FeSO4 => thu muối e) 2KHSO4 + 2NaHCO3 → K2SO4 +