Question

In: Chemistry

Balance by the half-reaction method, both in acid and in base: Cr2O3 (s) + H2O2 (aq)...

Balance by the half-reaction method, both in acid and in base:

Cr2O3 (s) + H2O2 (aq) -----> CrO42- (aq) + H2O (l)

Reductant half-reaction:

Oxidant half-reaction:

Net ionic full reaction in acid:

Net ionic full reaction in base:

Solutions

Expert Solution

In acidic media :

+3 -1 +6 -2

Cr2O3 (s) + H2O2 (aq) -----> CrO42- (aq) + H2O (l)

Reductant half-reaction: H2O2 (aq) -----> H2O (l)

Balance O atoms : H2O2 (aq) -----> H2O (l) + H2O(l)

Balance H atoms   H2O2 (aq) +2H+(aq) -----> 2H2O (l)

Balance charge : H2O2 (aq) +2H+(aq) +2e- -----> 2H2O (l) ----(1)

Oxidant half-reaction: Cr2O3 (s) -----> CrO42- (aq)

Balance Cr atoms : Cr2O3 (s)  -----> 2CrO42- (aq)

Balance O atoms : Cr2O3 (s)+5H2O (l) -----> 2CrO42- (aq)

Balance H atoms : Cr2O3 (s)+5H2O (l)  -----> 2CrO42- (aq) + 10 H+(aq)

Balance charge : Cr2O3 (s)+5H2O (l)  -----> 2CrO42- (aq) + 10 H+(aq) + 6e- -----(2)

[3x(1)] + (2) gives Cr2O3 (s)+5H2O (l) +3H2O2 (aq) +6H+(aq) -----> 6H2O (l) + 2CrO42- (aq) + 10 H+(aq)

This was the balanced reaction

In basic media :

+3 -1 +6 -2

Cr2O3 (s) + H2O2 (aq) -----> CrO42- (aq) + H2O (l)

Reductant half-reaction: H2O2 (aq) -----> H2O (l)

Balance O atoms : H2O2 (aq) -----> H2O (l) + H2O(l)

Balance H atoms   H2O2 (aq) + 2H2O (l)   -----> 2H2O (l) + 2OH-(aq)

Balance charge : H2O2 (aq) +2e- -----> 2OH-(aq) ----(1)

Oxidant half-reaction: Cr2O3 (s)  -----> CrO42- (aq)

Balance Cr atoms : Cr2O3 (s)  -----> 2CrO42- (aq)

Balance O atoms : Cr2O3 (s)+5H2O (l)  -----> 2CrO42- (aq)

Balance H atoms : Cr2O3 (s)+5H2O (l) +10OH- (aq) -----> 2CrO42- (aq) + 10 H2O (l)

Balance charge : Cr2O3 (s)+10OH- (aq) -----> 2CrO42- (aq) + 5H2O (l)  + 6e- -----(2)

[3x(1)] + (2) gives Cr2O3 (s)+10OH- (aq) +3H2O2 (aq) -----> 6OH-(aq)+ 2CrO42- (aq) + 5H2O (l)  

This was the balanced reaction


Related Solutions

balance each of the following oxidation/reduction reactions utilizing the half reaction method, H2O2 (aq) + Cl2O7...
balance each of the following oxidation/reduction reactions utilizing the half reaction method, H2O2 (aq) + Cl2O7 (aq) → ClO2- (aq) + O2 (g) in basic solution
(a) Balance the following half-reactions by the ion-electron half-reaction method: (i) (acid solution) NO3 – (aq)...
(a) Balance the following half-reactions by the ion-electron half-reaction method: (i) (acid solution) NO3 – (aq) → N2O (g) (ii) (acid solution) FeO4 2– (aq) → Fe3+ (aq) (iii) (base solution) Fe2O3 (s) → Fe(OH)2 (s) (iv) (base solution) Cu2O (s) → Cu(OH)2 (s) (b) Which of the above equations are oxidation half-reactions? (c) Give the formulas of the reactants that become oxidized in the course of the reaction.
Balance the following chemical reaction by the half reaction by the half reaction method under both...
Balance the following chemical reaction by the half reaction by the half reaction method under both acidic and basic conditions. What was oxidized and what was reduced? IrO3 + V(OH)4+2 → Ir(OH)5+3 + V+2
Balance the following oxidation-reduction reactions using the half-reaction method. a) S2-(aq) + NO3-(aq) ---> S8(s) +...
Balance the following oxidation-reduction reactions using the half-reaction method. a) S2-(aq) + NO3-(aq) ---> S8(s) + NO2(g) acidic solution b) MnO4-(aq) + I-(aq) ---> MnO2(s) + IO3-(aq) basic solution c) Sb(s) + H2SO4(aq) ---> Sb2(SO4)3(s) + SO2(g) acidic solution
Complete and Balance the following half-reactions (steps2-5 in half reaction method): MnO4−(aq) ⟶ Mn2+(aq) (in acidic...
Complete and Balance the following half-reactions (steps2-5 in half reaction method): MnO4−(aq) ⟶ Mn2+(aq) (in acidic solution)
4Au(s) + 16KCN(aq) + 3O2(g) + 6H2O(l) --> 4KAu(CN)4(aq) + 12KOH(aq) Balance using half reaction method....
4Au(s) + 16KCN(aq) + 3O2(g) + 6H2O(l) --> 4KAu(CN)4(aq) + 12KOH(aq) Balance using half reaction method. show all steps and please explain how you get the equation in each step
4Au(s) + 16KCN(aq) + 3O2(g) + 6H2O(l) --> 4KAu(CN)4(aq) + 12KOH(aq) Balance using half reaction method....
4Au(s) + 16KCN(aq) + 3O2(g) + 6H2O(l) --> 4KAu(CN)4(aq) + 12KOH(aq) Balance using half reaction method. show all steps
The question asks me to balance the following redox equation using the half-reaction method: 6) H2O2...
The question asks me to balance the following redox equation using the half-reaction method: 6) H2O2 (aq) + IO31- (aq) --> I1- (aq) + O2 (g) (acidic solution)
Balance the half-reactions assuming that they occur in acidic solution. H2O2(aq)?H2O(l) Zn(s)?Zn^2+(aq) Ti^3+(aq)?TiO2(s) Mn(s)?Mn^2+(aq)
Balance the half-reactions assuming that they occur in acidic solution. H2O2(aq)?H2O(l) Zn(s)?Zn^2+(aq) Ti^3+(aq)?TiO2(s) Mn(s)?Mn^2+(aq)
Balance the following redox reactions, in base, using the half-reaction method. Clearly identify each balanced half-reaction...
Balance the following redox reactions, in base, using the half-reaction method. Clearly identify each balanced half-reaction and the overall balanced equation. C3H8O2 (a) + Cr2O72– (aq)  C3H4O4 (aq) + 2 Cr3+ (aq)
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT