Polypropylene food containers can be shredded and recycled into new durable products, or they can be incinerated to release energy, producing carbon dioxide.

Which stage of a life cycle assessment (LCA) would contain this information?

• Disposal at the end of useful life
• Extracting and processing raw materials
• Manufacturing and packaging
• Use and operation during lifetime

Propene is the monomer used to produce polypropylene. Propene is obtained from crude oil.

Which two processes are used to produce propene from crude oil?

• Cracking
• Crystallisation
• Electrolysis
• Fermentation
• Fractional distillation

Table 1 shows the effect of heating on two different polymers used in household items.

Table 1

What type of polymer is Polymer A?

Why does Polymer A behave differently to Polymer B when heated? You should refer to crosslinks in your answer.