Pearson - 9Eb - Polymers

What is a polymer?

• A type of metal

• A solid crystal

• A long chain of molecules

• A short chain of atoms

How are the atoms in a polymer held together?

• By magnetic forces

• By ionic bonds

• By covalent bonds

• By cross-links

What happens to rubber when it is heated?

• It becomes harder

• It becomes soft and sticky

• It turns into a gas

• It loses its shape permanently

What is vulcanisation?

• A process that makes rubber softer

• A process of heating rubber with sulphur, that forms cross-links in rubber

• A way to extract crude oil

• A method of making synthetic polymers

What is a property of vulcanised rubber?

• It is a liquid

• It is sticky

• It can be stretched

• It is hard and tough

What is the monomer used to make poly(ethene)?

• Propene

• Chloroethene

• Ethene

• Tetrafluoroethene

What type of reaction is addition polymerisation?

• Endothermic

• Exothermic

• Catalytic

• Electrolytic

Which of the following is a natural polymer?

• Teflon

• Poly(propene)

• Poly(chloroethene)

• Rubber

What is a property of poly(propene)?

• It is strong and waterproof

• It is weak and brittle

• It is only used for packaging

• It is a gas at room temperature

What happens to rubber if too many cross-links are formed?

• It becomes a liquid

• It loses its elasticity

• It can stretch more easily

• It becomes more flexible