Degradable Polymers (Cambridge (CIE) A Level Chemistry): Exam Questions

Exam code: 9701

29 mins4 questions
1a
1 mark

State what is meant by the term hydrolysis.

1b
2 marks

State the reagents and conditions required for the acid hydrolysis of a polyamide.

1c
2 marks

Fig. 1.1 shows a section of a polyamide.

Section of a polyamide polymer chain showing repeating amide linkages

Fig. 1.1

Draw the skeletal formulae of the organic products formed when the polyamide is treated with dilute acid and heated under reflux.

1d
2 marks

Draw the skeletal formulae of the organic products formed when the polyamide in Fig. 1.1 is treated with excess aqueous sodium hydroxide and heated under reflux.

1a
3 marks

Fig. 1.1 shows a section of a nylon polymer.

Section of a nylon polyamide polymer chain showing repeating amide linkages

Fig. 1.1

i) Draw the skeletal formulae of the two monomers that could be used to make this nylon.

[2]

ii) State the type of polymerisation involved in the formation of this nylon.

[1]

1b
2 marks

Explain why clothing made from nylon is easily damaged by spillages of strong acids or strong alkalis.

1c
2 marks

Fig. 1.2 shows the structure of Nomex, an aromatic polyamide.

Structure of the Nomex aromatic polyamide repeat unit showing benzene rings and amide linkages

Fig. 1.2

Explain why Nomex has a higher melting point than nylon.

1d
3 marks

i) Draw the skeletal formulae of the two monomers used to manufacture Nomex.

[2]

ii) State the formula of the by-product formed during this polymerisation reaction.

[1]

2a
3 marks

i) Name an example of a synthetic polyester and a synthetic polyamide. 

[2]

 ii) Polyesters and polyamides are formed by condensation reactions. 

Name a molecule which is commonly eliminated in such reactions. 

[1]

2b
2 marks

Table 2.1 shows the repeat units of a number of polymers. Place a tick () against the ones which are biodegradable.

Table 2.1

Table showing the repeat units of four polymers A, B, C and D for biodegradability identification
2c
2 marks

Draw the structural formulae of the two monomers used to form polymer B.

3a
2 marks

Table 1.1 shows the structural formulae of three amino acids.

Table 1.1

Amino Acid

Structural formula

T

CH3CH(NH2)CO2H

U

C6H5CH2CH(NH2)CO2H

V

H2N(CH2)4CH(NH2)CO2H

State which of the amino acids, T, U or V, has the highest pH in an aqueous solution, and explain your answer.

amino acid ......................................................

explanation ......................................................

3b
1 mark

State how many different dipeptides could be formed from a reaction mixture consisting of amino acids T and U.

3c
2 marks

Despite containing a high proportion of carbon and hydrogen atoms, many polypeptides are soluble in water. Explain why. In your answer, you should refer to the functional groups present in a polypeptide chain.