CHƯƠNG 4: PHẢN ỨNG OXI HÓA KHỬ
Câu 1 : phản ứng oxi hóa – khử thông thường
NH3 + O2 -------> NO + H2O
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Zn + H2SO4 -----> ZnSO4 + H2S + H2O
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Mg + HNO3 ------> Mg(NO3)2 + NH4NO3 + H2O
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MnO2 + HCl ( MnCl2 + Cl2( + H2O
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KMnO4 + HCl ( KCl + MnCl2 + Cl2( + H2O
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FeO + HNO3( Fe(NO3)3+N2O(+H2O
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KMnO4 + K2SO3+ H2O ( K2SO4 + MnO2 + KOH
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KMnO4 + FeSO4 + H2SO4( Fe2(SO4)3 + MnSO4 + K2SO4 + H2O
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Câu2 : phản ứng oxi hóa – khử nội phân tử
KClO3 ------> KCl + O2
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AgNO3 ------> Ag + NO2 + O2
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Cu(NO3)2 -------> CuO + NO2 + O2
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HNO3 -------> NO2 + O2 + H2O
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KMnO4 ------> K2MnO4 + O2 + MnO2
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Câu 3 : phản ứng tự oxi hóa – khử
Cl2 + KOH -------> KCl + KClO3 + H2O
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S + NaOH ------> Na2S + Na2SO3 + H2O
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I2 + H2O --------> HI + HIO3
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Câu 4 : phản ứng oxi hóa – khử có số oxi hóa là phân số
Fe3O4 + Al -----> Fe + Al2O3
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Fe3O4 + HNO3 -------> Fe(NO3)3 + NO + H2O
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CH3 – C / CH + KMnO4 + KOH ----> CH3 – COOK + K2CO3 + MnO2 + H2O
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CH3 – CH = CH2 + KMnO4 + H2O ----->CH3 – CH(OH) –CH2(OH) + MnO2 + KOH
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5 . Fe3O4 + HNO3( Fe(NO3)3 + NO( + H2O
Thay sản phẩm khí NO( lần lượt bằng NO2, N2O, N2, NH4NO3 rồi cân bằng.
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Câu5 : phản ứng oxi hóa – khử có nhiều chất khử
FeS2 + O2 -------> Fe2O3 + SO2
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FeS + KNO3 -----> KNO2 + Fe2O3 + SO3
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FeS2 + HNO3( Fe(NO3)3 + H2SO4 + NO2( + H2O
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FeS2 + HNO3 + HCl ( FeCl3 + H2SO4 + NO( + H2O
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Câu 6 : phản ứng oxi hóa – khử có só oxi hóa tăng giảm ở nhiều mức
Al + HNO3 -------> Al(NO3)3 + NO + N2O + H2O ( VNO : VN2O = 3 : 1)
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Al + HNO3 -------> Al(NO3)3 + NO + N2 + H2O ( nNO : nN2 = 3 : 2)
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FeO + HNO3 ------> Fe(NO3)3 + NO2 + NO + H2O (Biết tỉ lệ số mol NO2 : NO = a : b )
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FeO + HNO3 ------> N2O + NO + Fe(NO3)3 + H2O
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Al + HNO3 -------> Al(NO3)3 + NO + N2O + H2O
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Câu7 : phản ứng oxi hóa – khử có hệ số bằng chữ
1. M + HNO3( M(NO3)n + NO2( + H2O (Với M là kim loại hoá trị n)
Thay NO2( lần lượt bằng: NO, N2O, N2, NH4NO3 rồi hoàn thành phản ứng.
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M + H2SO4( M2(SO4)n + SO2( + H2O
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3. FexOy + HNO3( Fe(NO3)3 + NO( + H2O
Thay NO( lần lượt bằng NO2, N2O, N2, NH4NO3 rồi hoàn thành phản ứng.
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Câu 8 : phản ứng oxi hóa – khử có chất hữu cơ
1. CH3- C / CH + KMnO4 + H2SO4 --------> CO2 + K2SO4 + MnSO4 + H2O
2. HOOC – COOH + KMnO4 + H2SO4 ------> CO2 + K2SO4 + MnSO4 + H2O
II. BÀI TẬP TRẮC NGHIỆM
Câu 1: Có các phát biểu sau: Quá trình oxi hoá là
(1) quá trình làm giảm số oxi hoá của nguyên tố.
(2) quá trình làm tăng số oxi hoá của nguyên tố.
(3) quá trình nhường electron.
(4) quá trình nhận electron.
Phát biểu đúng là
A. (1) và (3). B. (1) và (4). C. (3) và (4). D. (2) và (3).
Câu 2: Phản ứng nào dưới đây không là phản ứng oxi hoá-khử ?
A.Zn + H2SO4(( ZnSO4 + H2(
B. Fe(NO3)3 + 3NaOH (( Fe(OH)3