Balancing redox equation involving ethanol and dichromate ion [closed]

$$\ce{C2H6O(l) + Cr2O7^{2-}(aq) -> C2H4O2(aq) + Cr^3+(aq)}$$

Basically, I have written the half equations, but I have having trouble with converting ethanol to acetic acid ($$\ce{C2H6O -> C2H4O2}$$).

I do not know how to balance this. I tried adding $$\ce{H2O}$$ to either side but I didn't get an equal number of oxygens or hydrogens on either side.

• Duplicate. Does this help? chemistry.stackexchange.com/questions/140462/… Nov 23 '20 at 14:10
• @user55119 yes it is duplicate. Nov 23 '20 at 14:17
• More usual is using structural formulas of ethanol and acetic acid, as $\ce{C2H5OH + CH3COOH}$ Nov 23 '20 at 14:40

Of course you must add $$\ce{H2O}$$ on the left hand side, in order to compensate the excess of $$\ce{O}$$ atoms at right. Then add $$\ce{4 H+}$$ on the right hand side ! And $$4$$ electrons to compensate the charges. And that's over. $$\ce{C2H6O + H2O -> C2H4O2 + 4 H+ + 4 e-}$$. Where is the problem ?