## Chemistry and Chemical Reactivity (9th Edition)

a) The C=O bond, because it has the biggest difference in electronegativity between the ligands. b) There are 18 $\sigma$ bonds and 5 $\pi$ bonds. c) Yes, representing by [Ar] the aromatic ring: $\begin{smallmatrix} [Ar]&-&C&=&C&-&C&=&O&&&[Ar]&-&C&=&C&-&H\\ &&|&&|&&|&&&&&&&|&&|&&&&&\\ &&H&&H&&H&&&&&&&H&&HC&=&O&&&\\ \end{smallmatrix}$ d,e) All carbons are $sp^2$ hybridized because they make a double bond each, thus the angles 1, 2 and 3 are 120°.