1.1. This question is based on the chemistry of polymers.

Polyvinyl chloride (PVC) is a commonly used polymer.

State the term used to describe the units from which polymers are made and name the type of bonding between these units.

1.2. Figure 1 represents short chains of PVC.

Figure 1

Although hard material is used in water pipes and drains, PVC softens and melts when heated. 

Use the diagram and your knowledge of structure and bonding to explain why this occurs.

1.3. The basic unit of polyvinyl chloride is C₂H₃Cl.

The polymer chain consists of many of these base units bonded together.

In the space provided, draw a section of a chain of PVC showing three units joined together.