Balance using the ion-electron method

[anteater85]

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ClO3^- +AsO2 ^1- --> AsO4 ^3- + C^1-

the answer is:
ClO3 ^ 1- + 3 H2O + 3 AsO2 ^1- ---> 3 As O4 ^3- + Cl ^ 1- + 6 H^1+

I get lost between the steps...can someone go through this question step by step with me?
THx a lot

 

[nze82]

ClO3^- +AsO2 ^1- --> AsO4 ^3- + C^1-

the answer is:
ClO3 ^ 1- + 3 H2O + 3 AsO2 ^1- ---> 3 As O4 ^3- + Cl ^ 1- + 6 H^1+

I get lost between the steps...can someone go through this question step by step with me?
THx a lot

A) Separate your two half reactions:

ClO3-1 --> Cl-1 ...Cl's oxidation # changes from +5 to -1 = gain of 6e-

AsO2-1 --> AsO4 ...As's oxidation # changes from +3 to +5 = loss of 2e-

B) Start with balancing the least abundant elements (Cl and As):

ClO3-1 --> Cl-1

AsO2-1 --> AsO4 3-
C) Proceed with balancing Oxygen by adding H2O:

ClO3-1 --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3-
D) Balance H by adding H+:

ClO3-1 + 6H+ --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3- + 4H+
E) Balance the charge by adding electrons:

ClO3-1 + 6H+ + 6e- --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3- + 4H+ + 2e-

F) Multiply by proper coefficients to cancel out e-:

1[ClO3-1 + 6H+ + 6e- --> Cl-1 + 3H2O]

3[AsO2-1 + 2H2O --> AsO4 3- + 4H+ + 2e-]
*********************************
ClO3-1 + 3AsO2-1 + 3H2O --> Cl-1 + 6H+ + 3AsO4 3-

 

[anteater85]

A) Separate your two half reactions:

ClO3-1 --> Cl-1 ...Cl's oxidation # changes from +5 to -1 = gain of 6e-

AsO2-1 --> AsO4 ...As's oxidation # changes from +3 to +5 = loss of 2e-

B) Start with balancing the least abundant elements (Cl and As):

ClO3-1 --> Cl-1

AsO2-1 --> AsO4 3-
C) Proceed with balancing Oxygen by adding H2O:

ClO3-1 --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3-
D) Balance H by adding H+:

ClO3-1 + 6H+ --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3- + 4H+
E) Balance the charge by adding electrons:

ClO3-1 + 6H+ + 6e- --> Cl-1 + 3H2O

AsO2-1 + 2H2O --> AsO4 3- + 4H+ + 2e-

F) Multiply by proper coefficients to cancel out e-:

1[ClO3-1 + 6H+ + 6e- --> Cl-1 + 3H2O]

3[AsO2-1 + 2H2O --> AsO4 3- + 4H+ + 2e-]
*********************************
ClO3-1 + 3AsO2-1 + 3H2O --> Cl-1 + 6H+ + 3AsO4 3-

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