Predicting the Type of Polymerisation (Cambridge (CIE) A Level Chemistry): Exam Questions

Fig. 2.1 shows the structure of dehydroalanine.

Fig. 2.1

State the name of the functional group in dehydroalanine that is not present in most naturally occurring amino acids.

Dehydroalanine can undergo addition polymerisation.

Draw one repeat unit of the addition polymer formed by dehydroalanine.

The catalytic hydrogenation of dehydroalanine produces alanine, CH₃CH(NH₂)COOH.

Draw a section of the condensation polymer formed by alanine showing two repeat units. The peptide bond must be shown fully displayed.

Glycine and serine are amino acids with the systematic names 2-aminoethanoic acid and 2-amino-3-hydroxypropanoic acid respectively.

Draw the structural formulae of glycine and serine.

Serine exists as a pair of optical isomers. The three-dimensional structure of one optical isomer is shown in Fig. 3.2.

Fig. 3.2

Draw the three-dimensional structure of the other optical isomer of serine.

Glycine and serine can react to form condensation polymers containing ester and amide linkages.

State the names of the functional groups that react to form:

i) an ester linkage

[1]

ii) an amide linkage

[1]