✔ 最佳答案
1.
BrO3-(aq) + 6H+(aq) + 6e- → Br-(aq) + 3H2O(l) ... (*)
2I-(aq) → I2(aq) + 2e- ... (**)
(*) + 3x(**)
BrO3-(aq) + 6H+(aq) + 6I-(aq) →Br-(aq) + 3H2O(l) + 3I2(aq)
2.
MnO2(aq) + 4H+(aq) + 2e- → Mn2+(aq) + 2H2O(l) ... (*)
2Cl-(aq) → Cl2(g) + 2e- ... (**)
(*) + (**)
MnO2(aq) + 4H+(aq) + 2Cl-(aq) →Mn2+(aq) + 2H2O(l) + Cl2(g)
3.
KMnO4(s) + 8H+(aq) + 5e- → K+(aq) + Mn2+(aq) + 4H2O(l) ... (*)
2Cl-(aq) → Cl2(g) + 2e- ... (**)
2x(*) + 5*(**)
2KMnO4(s) + 16H+(aq) + 10Cl-(aq) → 2K+(aq) + 2Mn2+(aq) + 8H2O(l) + 5Cl2(g)
Assume that KMnO4 dissolves before reaction, the equation becomes :
2MnO4-(s) + 16H+(aq) + 10Cl-(aq) → 2Mn2+(aq) + 8H2O(l) + 5Cl2(g)