Compare and explain the relative acidities of butanoic acid, ethanol, ethanoic acid and water.
The three carboxylic acids methanoic acid, $\text{HCO}_2\text{H}$, ethanedioic acid, $\text{HO}_2\text{CCO}_2\text{H}$, and butanedioic acid, $\text{HO}_2\text{CCH}_2\text{CH}_2\text{CO}_2\text{H}$, are examined. Two tests were performed on separate samples of each organic acid, as shown. The results obtained are listed below. $\checkmark$ = observed change, $\times$ = no observed reaction.
Fill in the table with the reagents and conditions and the observed change for a positive test. Assume that these organic acids all have a similar acid strength.
Each compound, $\text{HCO}_2\text{H}$, $\text{HO}_2\text{CCO}_2\text{H}$ and $\text{HO}_2\text{CCH}_2\text{CH}_2\text{CO}_2\text{H}$, is dissolved separately in $\text{CDCl}_3$. Proton ($^1\text{H}$) NMR and carbon-13 ($^{13}\text{C}$) NMR spectra are then recorded. Complete the table.
The proton NMR spectrum of $\text{HCO}_2\text{H}$ in $\text{D}_2\text{O}$ is obtained. Describe and explain the difference seen between this spectrum and the proton NMR spectrum of $\text{HCO}_2\text{H}$ in (b)(ii).
$1,4$-dibromobutane, $\text{Br(CH}_2)_4\text{Br}$, is used in the synthesis of the dicarboxylic acid $\text{J}$ and diamine $\text{K}$ as shown.\n\nDraw the structures of $\text{G}$ and $\text{H}$ in the boxes.
Suggest reagents and conditions for each of steps $1$ to $4$.\n\nstep $1$\n\nstep $2$\n\nstep $3$\n\nstep $4$
Polyamide $\text{L}$ can be synthesised from dicarboxylic acid $\text{J}$, $\text{HO}_2\text{C(CH}_2)_2\text{CO}_2\text{H}$, and diamine $\text{K}$, $\text{H}_2\text{N(CH}_2)_6\text{NH}_2$.\n\nDraw the repeat unit of the polymer formed in the box. Any functional groups should be shown displayed.