Alcohol, Phenols and Ethers · Chemistry · COMEDK
MCQ (Single Correct Answer)
4 statements are given below. Identify the incorrect statement
A. Phenol has lower $$\mathrm{pK}_{\mathrm{a}}$$ value than $$\mathrm{p}$$-cresol
B. 2-Chlorophenol is more acidic than phenol
C. Ortho and para nitrophenols can be separated by steam distillation since $$\mathrm{p}$$-Nitrophenol is more steam volatile than o-Nitrophenol
D. Phenol on reaction with $$\frac{\mathrm{Cr}_2 \mathrm{O}_7^{2-}}{\mathrm{H}^{+}}$$ yields a conjugated diketone
Two statements, Assertion and Reason are given below. Choose the correct option.
Assertion: n-propyl tert-butyl ether can be readily prepared in the laboratory by Williamson's synthesis.
Reason: The reaction occurs by $$\mathrm{S}_{\mathrm{N}} 1$$ attack of Primary alkoxide on Tert-alkyl halide to give good yield of the product, n-propyl tert-butyl ether.
Compounds $$\mathrm{A}$$ and $$\mathrm{B}$$, having the same molecular formula $$(\mathrm{C}_4 \mathrm{H}_8 \mathrm{O})$$, react separately with $$\mathrm{CH}_3 \mathrm{MgBr}$$, followed by reaction with dil. $$\mathrm{HCl}$$ to form compounds $$\mathrm{X}$$ and $$\mathrm{Y}$$ respectively. Compound $$\mathrm{Y}$$ undergoes acidic dehydration in presence of Conc. $$\mathrm{H}_2 \mathrm{SO}_4$$ much more readily than $$\mathrm{X}$$. Compound $$\mathrm{Y}$$ also reacts with Lucas reagent, much more readily than $$\mathrm{X}$$, with appearance of turbidity. Identify $$\mathrm{X}$$ and $$\mathrm{Y}$$.
An organic compound $$[\mathrm{A}]\left(\mathrm{C}_5 \mathrm{H}_{12} \mathrm{O}\right)$$, on reaction with conc. $$\mathrm{H}_2 \mathrm{SO}_4$$ at $$443 \mathrm{~K}$$ gives $$[\mathrm{B}]$$ as one of the products. Compound [B] undergoes further reaction with $$\mathrm{O}_3$$ and $$\mathrm{Zn} / \mathrm{H}_2 \mathrm{O}$$ to give Propanone and Ethanal as products. Identify compound [A]
Match the compounds given in column I with the corresponding most stable Carbocations formed by each, as given in Column II, when they undergo acidic dehydration in presence of Conc. $$\mathrm{H}_2 \mathrm{SO}_4$$.
No. | Column I | No. | Column II |
---|---|---|---|
A | 2-Methylbutan-1-ol | P | $${(C{H_3})_2}\mathop C\limits^ + - CH{(C{H_3})_2}$$ |
B | Butan-2-ol | Q | $$C{H_3} - C{H_2} - C{H_2} - \mathop C\limits^ + {H_2}$$ |
C | 3, 3-Dimethylbutan-2-ol | R | $${(C{H_3})_2}\mathop C\limits^ + - C{H_2} - C{H_3}$$ |
D | Butan-1-ol | S | $$C{H_3} - \mathop C\limits^ + H - C{H_2} - C{H_3}$$ |
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Identify the starting compound from the following data:
$$\mathrm{C}_6 \mathrm{H}_{14} \mathrm{O}(\mathrm{X})$$ on reaction with $$\mathrm{HI}$$ yields a haloalkane (A) and an alcohol (B). Compound (A) on reaction with aqueous $$\mathrm{NaOH}$$ gives an alcohol (C). Compounds (B) and (C) on reaction with $$\mathrm{CrO}_3$$ in anhydrous medium yields Butanone and Ethanal respectively.
Choose the incorrect statement.
Choose the correct order of increasing acidic strength of the following compounds.
The chemical formula of Lucas reagent is
Which of the following is a false statement?
The major product in the given reaction is
Denatured alcohol is