... Fe + + 2e Câu 15: Chọn D 3Fe + 2O2 → to Fe3O4 Fe3O4 + 4H2SO4 →FeSO4 + Fe2(SO4)3 + 4H2O FeSO4 + 2NaOH → Fe(OH )2 ↓+Na2SO4 Fe2(SO4)3+ 6NaOH → 2Fe(OH)3↓ +3Na2SO4 Fe(OH )2 + 1 O2 + H2O → Fe(OH)3 - ... TN2: nHCl ( 2) = 0, 02 − 0, 05 = 0 ,15 nNa2CO3 − nHCl ( 2) = 0 ,15 → V = 0 ,15 ( l ) Câu 26 : Chọn B Theo X CH2=CH-COONH3CH3; CH2=CH-COONH3CH3+NaOH →CH2=CH-COONa+CH3NH2+H2O ⇒ n muối = nX = 0 ,15 mol ⇒ ... CuSO4 + H 2O → 2Cu + O2 + H SO4 0, 02 ¬ 0,01 H SO4 + MgO → MgSO4 + H 2O 0, 02 ¬ 0, 02 nH SO4 = nMgO = 0, 448 0,8 = 0, 02 → nCu = nCl2 = 0, 01 = 0, 02 → nO2 = 0, 01 nCl2 + nO2 = 22 , 40 Khối lượng...