7.9.5 Phenol

Questions

Section A

For each of the questions only one of the lettered responses (A – D) is correct.

Select the correct response in each case and mark its code letter by connecting the dots as illustrated on the answer sheet.

Section B

Answer all questions in the spaces provided.

1 Phenol, which is used to make plastics, is manufactured from propene and benzene as shown below:

propene

stage X stage Y acid

+ cumene compound A phenol + B

benzene

(a) (i) Write a balanced equation for stage X.

[2]

(ii) State three conditions used commercially in stage X and suggest why these particular conditions have been chosen.

[6]

(ii) What substance is added at stage Y and why?

[2]

(iii) Draw the structural formula for compound A

[1]

(iv) What is the name of the organic product B?

[1]

(b) (i) What is observed when phenol reacts with bromine water

[2]

(ii) Write a balanced equation for the reaction and name the organic product.

[3]

NI Specimen

2 Robert Lister was the first to use phenol as an antiseptic, saving the life of a young boy who had been in a traffic accident. At that time phenol was known as “carbolic acid”.

(a) (i) Draw the structural formula of phenol.

[1]

(ii) When phenol is added to water, a weakly acidic solution is formed. Write an equation explaining this observation.

[2]

(b) Phenol reacts with bromine to make tribromophenol, which is analogous to the commercially available antiseptic trichlorophenol (TCP). Write the equation for the reaction between bromine and phenol.

[2]

(c) Vinegar (ethanoic acid solution) also has medicinal properties. Explain how a solution of sodium hydrogencarbonate may be used to distinguish between a solution of vinegar and one of carbolic acid.

[2]

CHM3J8