22.4 Short Answer Questions 1) Why are there so many more carbon compounds than the number of compounds made up of all the rest of the elements combined? 2) What is meant by the term “structural isomer”? Draw a structural isomer of CH3-CH2-CH2-CH3. 3) What does the term “racemic mixture” mean? 4) Why doesn’t benzene typically undergo addition reactions like the alkenes do? 5) Which part of HCN, the hydrogen or the cyano group, adds to the O in a C=O bond and why? 6) Give the organic product of the following reaction.