a) Draw the equations of the oxidation of propanal to propanoic acid.
Propanal $\Rightarrow$ propanoic acid:
$CH_3CH_2CHO$ $-$ $2e^-$ $+$ $H_2O$ $\rightarrow$ $CH_3CH_2COOH$ $+$ $2H^+$
$MnO_4^-$ $+$ $5e^-$ $+$ $8H^+$ $\rightarrow$ $Mn^{2+}$ $+$ $4H_2O$
$5CH_3CH_2CHO$ $+$ $2MnO_4^-$ $ +$ $6H^+$ $\rightarrow$ $ 5CH_3CH_2COOH$ $ +$ $ 2Mn^{2+}$ $+$ $3H_2O$
There is a colour change from violet $(MnO_4^-)$ to very light pink $(Mn^{2+})$
b) Establish the equation that produces by esterification methyl butanoate!
$CH_3CH_2CH_2COOH$ $+$ $CH_3OH$ $\rightarrow$ $CH_3CH_2CH_2COOCH_3$ $+$ $H_2O$ Butanoic acid and methanol produce methyl butanoate and water
c) Produce benzoyl chloride from benzoic acid, then give the equation for the reaction that leads from there to the benzamide!
Benzoic acid and $P(V)$ chloride produce benzoyl chloride, chlorhydric acid and $P(V)$ oxychloride.
Benzoyl chloride and ammonia produce benzamide and ammonium chloride
