Balancing equations!!??

Question

1. __BrO3- + __Sb3+ > __Br- + __Sb5+ (acidic solution)

2. __C2H4+ + __MnO4- > __CO2 + __Mn2+ (acidic solution)

3. __NaOH+ __Ca(OH)2 + __C + __ClO2 > __NaClO2 + __CaCO3 + __H2O

4. __CrO4^2- + __Cl- > __Cr^3 + __HClO2

Answer 1

1. BrO3- + 3 Sb3+ + 6 H+ >> Br- + 3 Sb5+ + 3 H2O

2. 5 C2H4 + 12 MnO4- + 36 H+ >> 10 CO2 + 12 Mn2+ + 28 H2O

4 . 4 CrO42- + 3 Cl- + 23 H+ >> 4 Cr3+ + 3 HClO2 + 10 H2O

About the3rd question : are you sure that is correct ClO2 ?

Answer 2

BrO3- +6e- + 6H+ -> Br- + 3H2O
Sb3+ -> Sb5+ + 2e-

BrO3- + 3 Sb3+ +6 H+ -> Br- + 3 Sb5+ 3 H2O

MnO4- + 5e- + 8 H+ -> Mn2+ + 4 H2O