Why Aren't There Examples of Redox Reactions with 3 Half Reactions in Textbooks?

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The discussion centers on a redox reaction involving the compounds KBrO2, KI, and HBr, leading to the formation of KBr, I2, and H2O. The reaction is broken down into three half-reactions: the reduction of KBrO2 to KBr, the oxidation of KI to I2, and the interaction of HBr with K+ to form KBr. The participants debate whether the third half-reaction needs to be multiplied to balance charges, concluding that it should be multiplied by four to ensure proper cancellation of K+ ions. Ultimately, the balanced overall reaction is presented as KBrO2 + 4KI + 4HBr → 5KBr + 2H2O + 2I2. The discussion also highlights a lack of examples in textbooks for redox reactions involving three half-reactions, raising questions about educational resources on this topic.
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KBrO2 + KI + HBr ---> KBr + I2 + H2O

eq1
KBrO2 ---> KBr
4e- + 4H+ +KBrO2 ---> KBr + 2H2O

eq2
2KI ---> I2 + 2K+ + 2e-
4KI ---> 2I2 + 4K+ + 4e-

eq3
HBr ---> KBr
K+ + HBr ---> KBr + H+

since the charges in eq3 are +1=+1
you don't have to multiply this equation by 4 do you?

3H+ + KBrO2 + 4KI + HBr ---> 2KBr + 2H2O + 2I2 + 3K+


Haven't been able to find any examples or problems with
redox using 3 half reactions in any of my textbooks. Why
wouldn't they put a few in there?
 
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eq3
HBr ---> KBr
K+ + HBr ---> KBr + H+

multiply eq3 by 4 so K+ will cancel

4K+ + 4HBr ---> 4KBr + 4H+

adding all three:

KBrO2 + 4KI + 4HBr ---> 5KBr + 2H2O + 2I2
 
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