Suggest a reactant for conversion of ethanol to ethanal.
Ethanol can be oxidises into ethanal by using pyridinium chlorochromate. $\left(\mathrm{C}_6 \mathrm{H}_5 \stackrel{+}{\mathrm{N}} \mathrm{HCl} \overline{\mathrm{C}} \mathrm{CrOO}_3\right)$ in $\mathrm{CH_2Cl_2}$.
$\mathrm{H}_3 \mathrm{C}-\underset{\text { Ethanol }}{\mathrm{CH}_2}-\mathrm{OH} \xrightarrow{\mathrm{PCC} / \mathrm{CH}_2 \mathrm{Cl}_2} \mathrm{\mathop {C{H_3}}\limits_{Ethanal} - CHO}$
Suggest a reagent for conversion of ethanol to ethanoic acid.
Ethanol can be converted into ethanoic acid by using acidified $\mathrm{KMnO}_4$ or $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$. Both $\mathrm{KMnO}_4$ and $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ are strong oxidising agents.
$\underset{\text { Ethanol }}{\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH}} \xrightarrow{\substack{\text { Acidified } \\ \mathrm{KMnO}_4}} \underset{\text { Ethanoic acid }}{\mathrm{CH}_3 \mathrm{COOH}}$
Out of o-nitrophenol and p-nitrophenol, which is more volatile? Explain.
o-nitrophenol is more volatile than p-nitrophenol due to presence of intramolecular hydrogen bonding. In para nitrophenol intermolecular hydrogen bonding is present. This intermolecular hydrogen bonding causes the association of molecules.
Out of o-nitrophenol and o-cresol which is more acidic?
The acidic character of alcohols is due to the polar nature of $\mathrm{O}-\mathrm{H}$ bond. Higher the polarity of $\mathrm{O}-\mathrm{H}$ bond, more will be the acidic strength. Due to $-I$ and $-R$ effect of nitro group, electron density decreases in the $\mathrm{O}-\mathrm{H}$ bond of o-nitrophenol and thus polarity increases.
Whereas due to $+I$ effect of $-\mathrm{CH}_3$ group, electron density increases in the $\mathrm{O}-\mathrm{H}$ bond of o-cresol. Thus, $\mathrm{O}-\mathrm{H}$ bond of o-nitrophenol is weaker than $\mathrm{O}-\mathrm{H}$ bond of o-cresol and o-nitrophenol is more acidic than o-cresol.
When phenol is treated with bromine water, white precipitate is obtained. Give the structure and the name of the compound formed.
When phenol is treated with bromine water, white ppt. of 2, 4, 6 - tribromophenol is obtained.
