Download POLYMERS (Chemistry TIS)

Year
11
POLYMERS (Chemistry TIS)
WORKSHEET
1. Poly(ethene) is a plastic which is made by polymerizing ethene, C2H4.
(a) Which one of the following best describes the ethene molecules in this reaction? Put a ring around the
correct answer.
alcohols
alkanes
monomers
polymers
products
[1]
(b) The structure of ethane is shown below.
Explain, by referring to its bonding, why ethane cannot be polymerized. [1]
2. Before petroleum is fractionated, it is often heated to remove dissolved natural gas. Most of this natural
gas is methane, CH4. Draw a diagram to show how the electrons are arranged in methane.
show hydrogen electrons as •
show carbon electrons as 
[2]
(a) Methane, ethane and propane belong to a particular homologous series of compounds. State the name of
the homologous series to which these three compounds belong. [1]
3. Ethene can be polymerised to form poly(ethene).
(i) Complete the equation below to show the structure of two units in the poly(ethene) molecule. [1]
(ii) State the name given to this type of polymerisarion. [1]
March 2014
Mr.K.PRABAGARAN NAIR
COVER WORK
POLYMERS (Chemistry TIS)
Year
11
4. A South Korean chemist has discovered a cure for smelly socks. Small particles of silver are
attached to a polymer, poly(propene), and this is woven into the socks.
(a) (i) Give the structural formula of the monomer. [1]
(ii) Draw the structural formula of the polymer. [2]
(iii) Suggest which one, monomer or polymer, will react with aqueous bromine and why? [2]
(b) To show that the polymer contains silver the following test was carried out. The polymer fibres
were chopped into small pieces and warmed with nitric acid. The silver atoms were oxidised to
silver(I) ions. The mixture was filtered. Aqueous sodium chloride was added to the filtrate and a
white precipitate formed.
(i) Why was the mixture filtered? [1]
(ii) Explain why the change of silver atoms to silver ions is oxidation. [2]
(iii) Give the name of the white precipitate. [1]
March 2014
Mr.K.PRABAGARAN NAIR
COVER WORK
Year
11
POLYMERS (Chemistry TIS)
5. Polymers are extensively used in food packaging. Poly(dichloroethene) is used because gases can
only diffuse through it very slowly. Polyesters have a high thermal stability and food can be cooked
in a polyester bag.
(a) (i) The structure of poly(dichloroethene) is given below right.
Draw the structural formula of the monomer. [1]
(ii) Explain why oxygen can diffuse faster through the polymer bag than carbon dioxide can.
[2]
6. In 2002, Swedish scientists found high levels of acrylamide in starchy foods that had been
cooked above 120°C. Acrylamide, which is thought to be a risk to human health, has the structure
shown below.
(a) (i) It readily polymerises to polyacrylamide. Draw the structure of this polymer. [2]
March 2014
Mr.K.PRABAGARAN NAIR
COVER WORK
POLYMERS (Chemistry TIS)
Year
11
7. (a) (i) A polyester can be formed from the monomers HO-CH2CH2-OH and HOOC-C6H4-COOH.
Draw the structure of this polyester. [2]
(ii) Suggest what is meant by the term thermal stability. [1]
(c) (i) Describe two environmental problems caused by the disposal of plastic (polymer) waste. [2]
(ii) The best way of disposing of plastic waste is recycling to form new plastics. Explain how. [5]
(iii) What is another advantage of recycling plastics made from petroleum? [5]
March 2014
Mr.K.PRABAGARAN NAIR
COVER WORK