Which of the following represents $H$ückel's rule for aromaticity?

Find the products $(C)$ and $(E)$ in the following reaction sequences:
$n$-propyl bromide $\xrightarrow{Na} (A)$ $\xrightarrow[Al_2O_3/773 \ K]{CrO_3} (B)$ $\xrightarrow[500 \ K]{Cl_2/UV} (C)$
$n$-propyl bromide $\xrightarrow{Na} (A)$ $\xrightarrow[Al_2O_3/773 \ K]{CrO_3} (B)$ $\xrightarrow{CH_3Cl/AlCl_3} (D)$ $\xrightarrow{Cl_2/hv} (E)$

Which of the following statements about tropone is true?

Which aromatic compound has two double bonds and a five-membered ring?

All the hydrocarbons shown are very weak acids. One,however,is far more acidic than the others. Which one is the strongest acid?

Identify compound $A$ in the following reaction:
$\text{Benzene} + \text{ozone (excess)}$ $\rightarrow \text{Benzenetrizonide}$ $\xrightarrow{A} \text{glyoxal}$