Alcohols, Phenols and Ethers quiz

The IUPAC name of (CH3)3COH is:

Which reagent oxidises a primary alcohol to an aldehyde without further oxidation?

The Lucas reagent is:

Phenol reacts with bromine water to give:

Kolbe's reaction of sodium phenoxide with CO2 followed by acidification gives:

Which is the most acidic?

Reaction of a Grignard reagent with methanal followed by hydrolysis gives a:

Anisole on reaction with HI gives:

Cumene on oxidation followed by treatment with dilute acid gives phenol and:

Ethanol heated with concentrated H2SO4 at 443 K gives:

Why do alcohols have higher boiling points than hydrocarbons and ethers of comparable molecular mass? (2 marks)

Write the equation for hydroboration-oxidation of propene. What is the product? (2 marks)

Why is phenol more acidic than ethanol? (2 marks)

Give a chemical test to distinguish between ethanol and phenol. (2 marks)

Write the equation for preparation of methanol industrially from water gas. (2 marks)

Why are lower alcohols soluble in water while higher alcohols are not? (2 marks)

What happens when phenol is treated with concentrated nitric acid? Name the product and give one use. (2 marks)

Write the equation for the reaction of phenol with zinc dust. (2 marks)

Why does anisole undergo electrophilic substitution at ortho and para positions? (2 marks)

How is ethanol converted to ethanoic acid? Write the equation. (2 marks)

Calculate the volume of hydrogen at STP liberated when 3.2 g of methanol reacts completely with sodium (molar volume 22.4 L). (3 marks)

6.0 g of acetic acid reacts with excess ethanol in the presence of concentrated H2SO4. If the yield of ethyl acetate is 70%, calculate the mass of ester formed (CH3COOH = 60, CH3COOC2H5 = 88). (3 marks)

Calculate the mass of salicylic acid (C7H6O3 = 138) obtained from 9.4 g of phenol (C6H5OH = 94) by Kolbe's reaction, assuming 80% yield. (3 marks)

An alcohol has molecular formula C3H8O. Calculate its molar mass and percentage of oxygen. Draw its two alcohol isomers and one ether isomer. (3 marks)

Calculate the mass of oxygen required for the complete combustion of 23 g of ethanol, given C2H5OH + 3O2 -> 2CO2 + 3H2O. Also find the mass of CO2 produced. (3 marks)

Read the passage and answer the questions. A student was given three test tubes containing butan-1-ol, butan-2-ol and 2-methylpropan-2-ol. On adding Lucas reagent at room temperature, one turned cloudy immediately, another after about five minutes, and the third did not turn cloudy at room temperature. (i) Identify the alcohol in each tube. (ii) Explain the basis of the test. (iii) Write the reaction of the tertiary alcohol with the reagent. (5 marks)

Read the passage and answer the questions. In industry, phenol is made from cumene. Cumene is oxidised in the presence of air to cumene hydroperoxide, which is converted to phenol and another useful product by treating with dilute acid. (i) Write the equations involved. (ii) Name the by-product and give one use. (iii) Give another method for preparing phenol from benzene. (5 marks)

Read the passage and answer the questions. Phenol undergoes electrophilic substitution more readily than benzene. With dilute nitric acid at 298 K, it gives a mixture of ortho and para nitrophenols, which can be separated by steam distillation. (i) Why is phenol more reactive than benzene? (ii) Why can the two isomers be separated by steam distillation? (iii) Which isomer is more acidic? Explain. (5 marks)

Read the passage and answer the questions. A chemist wanted to prepare tert-butyl methyl ether. He first tried reacting tert-butyl bromide with sodium methoxide, but obtained an alkene. He then reacted sodium tert-butoxide with methyl bromide and obtained the ether. (i) Name the reaction used. (ii) Why did the first method give an alkene? (iii) Write the equation for the successful method. (5 marks)

Read the passage and answer the questions. Ethanol is produced commercially by fermentation of molasses. Yeast enzymes convert sugars into ethanol in the absence of air. If air enters, the ethanol may be converted into a sour substance. (i) Name the enzymes and write the equations. (ii) What is formed when air enters and why? (iii) Why is ethanol for industrial use denatured? (5 marks)

Describe the preparation of alcohols from alkenes, carbonyl compounds and Grignard reagents with equations. Draw a flowchart showing which carbonyl compound gives primary, secondary and tertiary alcohols with Grignard reagents. (6 marks)

Explain the acidic nature of phenol with resonance structures. Discuss the effect of electron-withdrawing and electron-releasing groups on its acidity, with examples. (6 marks)

Describe the electrophilic substitution reactions of phenol: nitration, halogenation, Kolbe's reaction and Reimer-Tiemann reaction, with equations and structures. (6 marks)

Describe the mechanism of dehydration of ethanol and the mechanism of formation of ethoxyethane. Draw a labelled energy profile or step diagram for each. (6 marks)

Describe the preparation of ethers by dehydration of alcohols and by Williamson synthesis. Explain the reaction of ethers with HI and electrophilic substitution in anisole, with structures. (6 marks)