Free Alcohols and Phenols MCQs with Answers
535 Alcohols and Phenols MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Alcohols are classified as primary, secondary or tertiary and studied through their hydrogen bonding, acidity, oxidation and reactions with active metals, acids and halogenating agents. Phenols require separate treatment because the hydroxyl group is attached to an aromatic ring, making their acidity and electrophilic substitution different from ordinary alcohols.
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Read the Alcohols and Phenols notesFree MDCAT chapter notes with key terms535 questions · page 26 of 27
- A. A
- B. B
- C. C
- D. D
Explanation: Carbons are numbered according to the placement of the -OH group. The carbon to which the OH group is attached is C1.
Correct answer: B- A. Phenol
- B. Ether
- C. Ethanol
- D. Methanol
Explanation: The antiseptic properties of phenol were used by Sir Joseph Lister (1827-1912).Phenol was one of the earliest disinfectants and…
Correct answer: Phenol- A. 1,3,6-Trinitrophenol
- B. m-Nitrophenol
- C. Tartaric acid
- D. Picric acid
Explanation: Picric acid, also called 2,4,6-trinitrophenol, is a pale yellow, odorless, crystalline solid that has been used as a military explosive…
Correct answer: Picric acid- A. The lone pair on the oxygen atom overlaps with the delocalized π- bonding system in benzene.
- B. Oxygen atom is directly bonded with the benzene ring in the phenoxide ion.
- C. The negative charge is localized on the oxygen atom of phenoxide ion.
- D. The negative charge is delocalized on oxygen atom of ethoxide ion.
Explanation: In phenoxide ion, the lone pair on the oxygen atom forms a delocalised pi system with the benzene ring by involving the electrons of the…
Correct answer: The lone pair on the oxygen atom overlaps with the delocalized π- bonding system in benzene.- A. Propane and methyl Grignard
- B. Methyl ethyl ketone and methyl
- C. Propanaldehyde and ethyl Grignard
- D. None of these
Explanation: The addition of Grignard reagent to aldehydes leads to the production of secondary alcohol, and the addition of ketone leads to the…
Correct answer: Propanaldehyde and ethyl Grignard- A. Cu
- B. CuO
- C. Cu2O
- D. Cu2O + Cu2O3
Explanation: Fehling solution is reduced by aldehydes and a red precipitate of Cu2O is obtained.
Correct answer: Cu2O- A. Diethyl ether
- B. Ethane
- C. Ethanal
- D. Ethanol
Explanation: When CH3CH2l reacts with dry Ag2O, the correct product formed is ethanol.
Correct answer: Ethanol- A. C2H6
- B. C2H2Cl
- C. CH3OCH3
- D. C2H5OH
Explanation: Among the given compounds, C2H5OH (ethanol) has the highest boiling point.
Correct answer: C2H5OH- A. Alkoxides
- B. Ethane
- C. Alkane
- D. Alloyed
Explanation: Alcohols react with sodium to form a salt (sodium alkoxide) and bubbles of hydrogen gas will be seen.
Correct answer: Alkoxides- A. Carbonal
- B. Methanol
- C. Ethanol
- D. Glycol
Explanation: (D) is correct because the product of this reaction is ethylene glycol, which is a colorless, odorless, and slightly viscous liquid.
Correct answer: Glycol- A. Witting reaction
- B. Tollen test
- C. Lucas test
- D. Ninhydrin test
Explanation: The Lucas test is commonly used to differentiate between primary, secondary, and tertiary alcohols.
Correct answer: Lucas test512. Rectified spirit is:
- A. 100% ethanol
- B. 95% ethanol
- C. 90% ethanol
- D. 35% ethanol
Explanation: Rectified spirit, also known as neutral spirits, is a high-purity ethanol solution that has undergone multiple distillation processes…
Correct answer: 95% ethanol- A. Alcohols
- B. Phenols
- C. Amino acids
- D. Carboxylic acids
Explanation: The Lucas test is a chemical test used to differentiate between primary, secondary, and tertiary alcohols.
Correct answer: Alcohols- A. Methanol
- B. Formaldehyde
- C. Formic acid
- D. Carbon dioxide gas
Explanation: The complete oxidation of methane in the presence of a copper catalyst at high pressure (200 atm) leads to the formation of methanol.
Correct answer: Methanol- A. CH3CH2OH + PCl5 →
- B. CH3CH2OH + Na →
- C. CH3CH2OH + PCl3 →
- D. CH3CH2OH + 5OCl →
Explanation: The correct answer is Option B: CH3CH2OH + Na →. In this reaction, sodium (Na), a metal, reacts with ethanol (CH3CH2OH) to form sodium…
Correct answer: CH3CH2OH + Na →- A. Primary alcohol
- B. Secondary alcohol
- C. Tertiary alcohol
- D. All of the above
Explanation: Ketones are prepared by the oxidation of secondary alcohols. When a secondary alcohol is oxidized, it loses hydrogen atoms and forms a…
Correct answer: Secondary alcohol- A. COCH3
- B. (CH 3)2 CHOH
- C. (CH3)3COH
- D. CH3CH2OH
Explanation: To undergo dehydrogenation, the compound must have OH group. Only compound in option A is not an alcohol thus, it is the correct answer.
Correct answer: COCH3518. To distinguish among primary, secondary and tertiary alcohols which of the following tests is used?
- A. Benedicts reagent
- B. Tollen's reagent
- C. Lucas test
- D. None of the above
Explanation: The lucas test is used to differentiate between primary, secondary and tertiary alcohols,an oily layer of alkyl halides separates out in…
Correct answer: Lucas test- A. Alkene
- B. Sodum alkoxide
- C. Alkane
- D. Ether
Explanation: When alcohols react with metals a salt is formed,the reaction when a monohydric alcohol reacts with sodium metal results in the production…
Correct answer: Sodum alkoxide- A. HCOOH (Formic Acid)
- B. CH3CH2COOH (Propanoic Acid)
- C. CH3OCH3 (Diethyl Ether)
- D. CH3COOH (Acetic Acid)
Explanation: The correct answer is CH3OCH3 (Diethyl Ether). Diethyl ether does not contain an active hydrogen atom that sodium can displace, unlike…
Correct answer: CH3OCH3 (Diethyl Ether)