Benzoic acid, c6h5co2h, dissolves in concentrated sulfuric acid to give a cation with the formula c6h5co2h+2 , where an oxygen atom has been protonated. there are two possible oxygen atoms for protonation in this molecule, but the experimental evidence suggests that only one protonated species is formed in measurable amounts. what is the structure of the ion formed, and why is it the only major product of the reaction?