Alcohols & phenols & ethers practice · Easy

Option A (Phenetole) is correct because sodium phenoxide reacts with ethyl iodide via Williamson ether synthesis to form phenetole (ethyl phenyl ether).

Option D ($100\mathrm{\% \;}{\mathrm{C}_2}{\mathrm{H}_5}\mathrm{OH}$) is correct because absolute alcohol is defined as pure ethanol without any water content.

Option B ($o -$nitrophenol) is correct because it exhibits intramolecular hydrogen bonding, which lowers its boiling point compared to other isomers.

Option C (Higher) is correct because thioethers have higher boiling points than ethers due to the larger size and greater polarizability of sulfur compared to oxygen, leading to stronger London dispersion forces.

Option D (2-methoxy propane) is correct because the methoxy group is attached to the second carbon of the propane chain.

Option C ($\mathrm{CHO}$—$\mathrm{CHO}$) is correct because glyoxal is a dialdehyde with the formula (CHO)₂.

Option A is correct because $\mathrm{PCl}_5$ readily replaces the hydroxyl group (OH) of alcohols with a chlorine atom.

Option C (Ether) is correct because Williamson's synthesis is a method for preparing ethers by reacting an alkoxide with a haloalkane.

Option B is correct because both the assertion and reason are true, but the reason doesn't explain why isopropyl alcohol is generally preferred over ethanol.

Option D (Alcohols) is correct because the Lucas test is used to differentiate between primary, secondary, and tertiary alcohols based on their reactivity with Lucas reagent (HCl and ZnCl₂).

Option B (${\mathrm{C}_6}{\mathrm{H}_5}\mathrm{COOH}$) is correct because aromatic carboxylic acids have a high carbon to hydrogen ratio, leading to incomplete combustion and sooty flames.

Option D (On reduction it yields phenol) is correct because the reduction of benzaldehyde yields benzyl alcohol, not phenol.

Option A (Butyne-1, 4-diol) is correct because acetylene reacts with formaldehyde in the presence of a copper acetylide catalyst to form but-2-yne-1,4-diol.

Option D is correct because phenol on sulfonation gives a mixture of ortho- and para-phenol sulfonic acids.

Option B is correct because phenol is weakly acidic due to the resonance stabilization of the phenoxide ion.

Option C is correct because phenol is used as a disinfectant and antiseptic for wounds, including those caused by animal bites.

Option A (Benzene ring exists in resonance) is correct because the resonance in the benzene ring of phenol stabilizes the phenoxide ion, making phenol more acidic than cyclohexanol.

Option D (${\mathrm{C}_2}{\mathrm{H}_5}\mathrm{Cl} + {\mathrm{C}_2}{\mathrm{H}_5}\mathrm{ONa}$) is correct because it represents a Williamson ether synthesis, which directly produces an ether.

Option B (${3^ \circ } > {2^ \circ } > {1^ \circ }$) is correct because the stability of the alkene formed during dehydrohalogenation increases with the degree of substitution.

Option D (34$^ \circ C$) is correct because diethyl ether has weaker intermolecular forces (van der Waals) than ethanol (hydrogen bonding), resulting in a lower boiling point.

Option C ($para$-nitrophenol) is correct because the nitro group is a strong electron-withdrawing group that stabilizes the phenoxide ion through resonance and inductive effects, making it the most acidic.

Option B (Diethyl ether) is correct because ethyl iodide reacts with dry Ag2O to form diethyl ether via Williamson's ether synthesis.

Option D (Pyridinium chlorochromate) is correct because PCC is a mild oxidizing agent that can convert a secondary alcohol to a ketone without oxidizing the alkene.

Option B (Ethylene glycol) is correct because it contains two hydroxyl (-OH) groups.

Option A ($\mathrm{C}{\mathrm{H}_3}\mathrm{OH}$) is correct because wood spirit is the common name for methanol.

Option D (2, 4, 6-trinitrophenol) is correct because 2,4,6-trinitrophenol, also known as picric acid, is a well-known explosive due to the presence of multiple nitro groups.

Option D (${\mathrm{C}_2}{\mathrm{H}_5}\mathrm{OH}$) is correct because ethanol is a small, polar molecule capable of forming hydrogen bonds with water, making it miscible in all proportions.

Option C (O - Nitro phenol > P - chloro phenol > Phenol > O - cresol) is correct because the acidity of phenols is affected by the substituents. Electron-withdrawing groups increase acidity, while electron-donating groups decrease acidity. Ortho-nitrophenol is more acidic than para-nitrophenol due to intramolecular hydrogen bonding making it easier to lose a proton.

Option A (${1^ \circ }$ alcohol) is correct because aldehydes are reduced to primary alcohols by $\mathrm{Zn}/\mathrm{HCl}$.

Option B is correct because carbolic acid is a common name for phenol.