Polymers can vary in density depending on the conditions they are made under and the monomers that have combined to form them. A common example is polyethene which is made in low density and high density forms for its different uses.

Plastics are a type of polymer produced by addition and condensation polymerisation. They can be classified into two groups - thermosetting polymers or thermosoftening polymers.

1

Sort the properties into those of LDPE, HDPE and those which they both exhibit.

2

Which type of plastic have covalent bonds linking the polymer molecules?

3

Which type of plastic is used in electrical fittings? Why?

4

What type of plastic will melt when heated?

5

Is the structure shown that of a thermosoftening or thermosetting plastic?