# Balancing complex haloform redox reaction

I just completed a haloform reaction experiment, using acetophenone and sodium hypochlorite to form benzoic acid and chloroform.

My lab report has a question regarding balancing the equation of the reaction. I have been working on it for quite a while, and I can't figure out how to do it. I've tried looking up methods but too many atoms are reliant on too many molecules! Can someone help with this question and explain how to do it so I can really understand this process?

I need to be able to identify the limiting reactant as well, which relies on the molar ratio of the reactant to the product, so I really need to know how to do this.

• This question is related, as it describes how to balance reactions in general without guesswork. I'm partial to my own answer involving matrices, but all the methods given as answers would work. – Tyberius Mar 30 '17 at 5:04
• just go by the mechanism, youll have every reactant over there, s those numbers are done, then just get the product numbers, in accordance with reactants – Supernova Mar 30 '17 at 6:40

As you noted, you need to find the limiting reactant. This is most of the time done by taking the one with a 1:1 ratio of educt:product.

So in this case, the $\ce{ROCH_3}$. So you take that once. Now you see immediately that you need 2 $\ce{Na}$ on the right side, so you can put a 2 in front of the $\ce{NaOH}$. You have two $\ce{X}$ on the left, but 4 on the right, so put a 2 in front of the left one. Now count all your atoms. Subtract them from each other:

You have $a * \ce{H}$ on the left and $b * \ce{H}$ on the right. if $a-b=0$ its balanced. Do that for every reactant and you're done.

There are of course more strictly formulated methods, but in my time I noticed that a straightforward approach with a little thinking can be applied most universally without having to memorize some formulas.

The coefficients should be

1 3 4 1 1 3 3, from left to right. The limiting reagent is acetophenone.

Used this website to find the answer.

http://www.chem.ucalgary.ca/courses/350/Carey5th/Ch18/ch18-3-2b.html

-- a fellow owl ;)

• It would likely help the OP more to have a method of finding an answer rather than just being told what it is. – Tyberius Apr 4 '17 at 14:02