State the relative acidities of bromoethanoic acid, $\mathrm{BrCH_2COOH}$, chloroethanoic acid, $\mathrm{ClCH_2COOH}$, ethanoic acid, $\mathrm{CH_3COOH}$ and ethanol, $\mathrm{CH_3CH_2OH}$. Explain your reasoning.
Fig. 7.1 shows the reaction of methylbenzene and ethanedioic acid with $\mathrm{KMnO_4}$. Predict the major carbon-containing product for each reaction.
Polyamide X may be prepared from ethanedioic acid and benzene-1,4-diamine. In the box, draw the repeat unit of Polyamide X. The new functional group formed must be shown in displayed form.
Benzene-1,4-diamine can be produced by reducing 1,4-dinitrobenzene. Complete the reduction equation. $[\mathrm{H}]$ stands for one atom of hydrogen from a reducing agent.
Fig. 7.2 shows the two-step synthesis of the azo compound W. Suggest structures for compounds V and W, and draw them in the boxes in Fig. 7.2.
Give the reagents and conditions for step 1.