# Are you good at $Balancing$?

Here's a problem I've been trying for ages.... $C_{2}H_{5}OH+ I_{2}+ OH^{-}\longrightarrow\ CHI_{3}+HCOO^{-}+H_{2}O$

$Question:$ Find the stoichiometric coefficients of each of the given compounds involved in the reaction by balancing it( preferably by oxidation no.or Ion-electron method).

Do try this question and post a nice solution for it! Note by Samarpit Swain
5 years, 9 months ago

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Sorry for the way too late response dude !!!

While balancing ignore $H_2 O$ and $OH^{-}$ keeping in mind that the medium is basic .(Basically we don't need them as such since they are bound to come in the scene at the end ) . Now, balance the rest i.e. $C_{2}H_{5}OH+ I_{2} \longrightarrow CHI_{3}+HCOO^{-}$ , you will get $2C_{2}H_{5}OH+ 3I_{2}+ 12OH^{-}\longrightarrow\ 2CHI_{3}+2HCOO^{-}+10H_{2}O$ but here you'll notice that the charge is not balanced on the RHS so I think the correct answer is $2C_{2}H_{5}OH+ 3I_{2}+ 12OH^{-}\longrightarrow\ 2CHI_{3}+2HCOO^{-}+10H_{2}O + 10e^{-}$

- 5 years, 9 months ago

I'm really, really sorry for the late response.

I think your method is absolutely fine, but are you sure that you can have excess electrons at the end of such reactions? I've never come across such an equation before.

Also the law of conservation of mass is violated(though negligibly), since most of the theoretical reactions give an ideal perspective.

- 5 years, 8 months ago

Well , I don't think we will be able to manage without the extra electrons . Do you have anything else in mind ?

@Ronak Agarwal , @Pranjal Jain , @Deepanshu Gupta : What would you guys have done ?

- 5 years, 8 months ago

I believe mechanism of iodoform reaction is the key.

- 5 years, 8 months ago

Can you explain it a bit more , please?

- 5 years, 8 months ago

See this. Replace $-R$ by $-H$ and the disproportionation of $I_2$ will be a bit different.

$3I_2+6OH^-\rightarrow 5I^-+IO_3^-+3H_2O$

Just add all elementary reactions to get stoichiometric coefficients.

- 5 years, 8 months ago

Thanks

- 5 years, 8 months ago

Have you tried taking $C_2H_5OH + I_2 \rightarrow CHI_3$ and $C_2H_5OH \rightarrow HCOO^-$ as the two half reactions and solving? Not going to post a full solution because exams.

- 5 years, 9 months ago

Yup, I've tried that way, didn't help:(

- 5 years, 9 months ago