Cannizzaro Reaction Hello I just finshed a Lab and this is what I got. I was won

Question

Cannizzaro Reaction

Hello I just finshed a Lab and this is what I got. I was wondering if I am going in the right path. It does not make sence how I got 392.66% yeild of 4-Cholorbenoic Acid.

Starting Material:

1.0166g 4-chlorobenzaldehyde

5.0315g KOH

What I got:

4-chlorobenzyl Alcohol = .385g

4-Cholorbenoic Acid = 2.33g

My professor told me its not a 1:1 calculation so this is how I did it.

My main question is am i right when I calculated the theoretical yield of 4-chlorobenzyl alcohol and 4-chlorobenzoic acid (moles and gram)? maybe that is the reason why my % yeild seems off?

Explanation / Answer

It is completely impractical to have obtained such a high yield of acid. Your calculations are correct and 2 molecules of aldehyde are consumed to give 1 molecule each of acid and alcohol.

I went through many web pages to search whether such a case has ever occured before, and it turns out that it is not possible. I would suggest going over your data again, may be some data is wrong, or you are missing out some factor. Check whether you took some other aldehyde as well alongside 4-chlorobenzaldehyde in the reactants, because in that case the cross cannizzaro reaction can produce the extra amount of acid which you are getting in your data.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.