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26
Subjective

What is denatured alcohol?

Explanation

Alcohol is used in large quantities in the manufacture of alcoholic liquors. Its continuous use damages the various vital organs. Therefore, to refrain the people from drinking alcohol, heavy excise duty is levied on the sale of alcoholic beverages. But, it is used in various industries as it is a very good solvent.

Therefore, industrial alcohol must be cheap. Thus, to provide cheaper alcohol to industries and to refrain people from drinking alcohol, it is mixed with some copper sulphate, pyridine, methyl alcohol or acetone.

Alcohol is made unfit for drinking by mixing some quantity of any of these substances in it. This is called denatured alcohol.

27
Subjective

Suggest a reagent for the following conversion.

Explanation

The given reactant is .

It is a secondary alcohol. Secondary alcohol gives ketone when oxidises by CrO$_3$ or pyridinium chlorochromate without carrying out oxidation at the double bond.

28
Subjective

Out of 2-chloroethanol and ethanol which is more acidic and why?

Explanation

2 -chloroethanol is more acidic than ethanol. Due to $-I$ effect (electron withdrawing group) of the Cl -atom electron density in $\mathrm{O}-\mathrm{H}$ bond decreases. So, $\mathrm{O}-\mathrm{H}$ bond of 2-chloroethanol becomes weaker than $\mathrm{O}-\mathrm{H}$ bond of ethanol. Thus, 2-chloroethanol is more acidic than ethanol.

Stronger acid due to $-I$ effect of Cl.

29
Subjective

Suggest a reactant for conversion of ethanol to ethanal.

Explanation

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 $\mathrm{CH_2Cl_2}$.

$\mathrm{H}_3 \mathrm{C}-\underset{\text { Ethanol }}{\mathrm{CH}_2}-\mathrm{OH} \xrightarrow{\mathrm{PCC} / \mathrm{CH}_2 \mathrm{Cl}_2} \mathrm{\mathop {C{H_3}}\limits_{Ethanal} - CHO}$

30
Subjective

Suggest a reagent for conversion of ethanol to ethanoic acid.

Explanation

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.

$\underset{\text { Ethanol }}{\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH}} \xrightarrow{\substack{\text { Acidified } \\ \mathrm{KMnO}_4}} \underset{\text { Ethanoic acid }}{\mathrm{CH}_3 \mathrm{COOH}}$