Unit 11: Alcohols, Phenols and Ethers

11. The general formula for alcohols is:

a) CnH2nC_nH_{2n}Cn​H2n​
b) CnH2n+2C_nH_{2n+2}Cn​H2n+2​
c) CnH2n+1OHC_nH_{2n+1}OHCn​H2n+1​OH
d) CnH2n−2C_nH_{2n-2}Cn​H2n−2​
Answer: c) CnH2n+1OHC_nH_{2n+1}OHCn​H2n+1​OH

12. Which of the following is an example of a primary alcohol?

a) 2-Butanol
b) 1-Butanol
c) 2-Methylpropanol
d) Cyclohexanol
Answer: b) 1-Butanol

13. The process of converting an alcohol to a ketone involves:

a) Oxidation
b) Reduction
c) Esterification
d) Hydrolysis
Answer: a) Oxidation

14. Which reagent is used to test for the presence of phenol?

a) Bromine water
b) Sodium hydroxide
c) Potassium permanganate
d) Hydrochloric acid
Answer: a) Bromine water

15. The reaction of alcohols with carboxylic acids to form esters is known as:

a) Esterification
b) Hydrolysis
c) Saponification
d) Oxidation
Answer: a) Esterification

16. In the preparation of ethers by the Williamson synthesis, the reactants include:

a) Alcohol and alkyl halide
b) Alcohol and carboxylic acid
c) Ether and acid chloride
d) Alcohol and ester
Answer: a) Alcohol and alkyl halide

17. Which of the following is a characteristic property of phenols?

a) Formation of esters with alcohols
b) Formation of phenoxide ions with sodium hydroxide
c) Formation of ketones with oxidizing agents
d) Reaction with carboxylic acids to form esters
Answer: b) Formation of phenoxide ions with sodium hydroxide

18. The product formed when phenol reacts with concentrated sulfuric acid is:

a) Phenol sulfate
b) Sulfonic acid
c) Phenol sulfonic acid
d) Sulfur dioxide
Answer: c) Phenol sulfonic acid

19. Which type of alcohol is generally most reactive towards oxidation?

a) Tertiary alcohol
b) Secondary alcohol
c) Primary alcohol
d) None of the above
Answer: c) Primary alcohol

20. The dehydration of alcohols to form alkenes typically requires:

a) Acidic catalyst
b) Basic catalyst
c) Neutral catalyst
d) Heat alone
Answer: a) Acidic catalyst