skogias6733 wrote:For this question I did it a different way i thought it wasnt B because reactants in B (5 carbons) dont have the same amount of carbons as the product? (7 carbons) and the other examples show that no carbons are being lost, only oxygen/hydrogen?
The answer is indeed B but you do have a good point: count carbons to be sure that you are not missing something.
However, you missed one thing! Look again at the model reaction given on page H2-45. Notice that the ketone appears one time but the aldehyde appears twice (science language: "one equivalent of 2-propanone + 2 equivalents of benzaldehyde). So when you are counting carbons in question 15, you must count the ketone once (3C) and the aldehyde twice (2C x 2 = 4C) which gives a total of 7C which is the structure provided.
