The preparation of “azo” dyes often does not work well in the laboratory. Although the correct colour is usually apparent, very little product is obtained. Seeing this, a student decides to modify the experimental procedure and obtains a record quantity of product. Being very competitive, he does not want to let you in on his trick. However, you noticed that he added a liquid, and that he was monitoring the addition with pH paper. Knowing this, can you explain his high yield?
Just look at the lab manual at the formation of the NO+ ion... adding HCl pushes the equilibrium to the right according to LeChatelier's principle, increasing the amount of diazonium salt and in turn of dye. But the student still checks with litmus so that it does not become too acidic (that's bad!).
Think a little bit before just posting the question and waiting for the answer... Otherwise you will do really bad on the final!
how do you synthesize 1-propanol from the starting material butyraldehyde?
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