Year 11 Chemistry

Organic and Polymer Chemistry Test

Section A: Multiple Choice Questions (20 marks)

Q1. Which of the following compounds is a hydrocarbon?

A. CH3CH2OH

B. C2H4

C. C6H12O6

D. diamond

Q2. A homologous series is a series of compounds in which the:

A. successive members differ by a –CH2- unit

B. all members have the same functional group

C. compounds have the same molecular formula but different structural formulae

D. compounds have different structural formulae but the same physical and chemical properties

Q3. The first three members of the homologous series of alcohols in order from smallest to largest is:

A. ethene, propene, butene

B. ethane, ethene, ethyne

C. propanol, propanoic acid, chloropropane

D. methanol, ethanol, propanol

Q4. In order to make the ester ‘ethyl ethanoate’ the three chemical compounds required are:

A. ethanol and ethanoic acid

B. propanol, ethanoic acid and hydrochloric acid

C. sulfuric acid, ethanoic acid and ethanol

D. methanoic acid, ethanoic acid and sulfuric acid

Q5. Two organic compounds are structural isomers if they have:

A. the same molecular formula but different structural formulae

B. the same structural formula but different molecular formulae

C. successive members which differ by a –CH2- unit

D. the same structural formulae but different orientations in three dimensional space

Q6. In the presence of UV light, ethane can react with chlorine gas to produce chloroethane and hydrogen chloride gas. This type of reaction can be classified as:

A. addition

B. condensation

C. substitution

D. combustion

Q7. Propane undergoes compete combustion in the presence of plentiful oxygen to produce carbon dioxide gas and water vapour. In order to balance the chemical equation for this reaction as shown below the values of the coefficients w, x, y and z must be:

wC3H8 (g) + xO2 (g) ® yCO2 (g) + zH2O (l)

A. 1, 3, 3, 4

B. 1, 5, 3, 4

C. 2, 9, 6, 8

D. 1, 3, 5, 5

Q8. Fractional distillation is a separation process employed in the refining of petroleum. Separation of the various fractions that make up petroleum is based on variations in:

A. boiling points of the molecules

B. strength of the dispersion forces between molecules

C. molecular weight of the molecules

D. all of the above

Q9. The petrochemical industry uses vast quantities of the alkenes (such as ethene) that are produced by catalytic cracking. Which of the following molecules is an alkene?

A. (CH3)2CH.CH3

B. CH3CH2NH2

C. CH3CHCH2

D. C6H6

Q10. Which of the following molecules is an isomer of butane?

A. pentane

B. 2-methyl-propane

C. butene

D. 3-methyl-butane

Q11. Which of the following statements best describes an unsaturated compound?

A. An unsaturated compound contains carbon, hydrogen and oxygen atoms

B. An unsaturated compound readily undergoes addition reactions

C. An unsaturated compound will not burn in air

D. An unsaturated compound undergoes condensation reactions to produce a saturated compound.

Q12. The chemical formula of an alkyne with 13 carbon atoms is:

A. C13H24

B. C13H26

C. C13H28

D. There is insufficient information to determine its formula

Q13. Which of the following descriptions is the most accurate statement of the properties of polychloroethene (also known as polyvinyl chloride, PVC)?

A. It is a linear, thermoplastic polymer

B. It is a crosslinked, thermoplastic polymer

C. It is a linear, thermosetting polymer

D. It is a crosslinked, thermosetting polymer.

Q14. Polyethene (also known as polyethylene) can be manufactured in two quite distinct forms: low density polyethene (LDPE) and high density polyethene (HDPE) by varying the conditions in which the polymer is produced. Compared to low density polyethene, HDPE has:

A. more crosslinks between polymer chains

B. less branches in its polymer chains, resulting in stronger dispersion forces

C. more flexibilty and a lower melting point

D. more branches in the polymer chains, making it less flexible

Q15. Consider the four polymers ‘nylon, polyester, polystyrene and bakelite’. The polymer that does NOT belong in this group due to the type of bonding exhibited between the monomers that make it up is:

A. nylon

B. polyester

C. polystyrene

D. bakelite

Q16. Nylon is a far stronger fibre than polyethene, even though both are linear polymers. The main reason for the difference in strength is that:

A. nylon exhibits hydrogen bonds between its chains whereas polyethene has only dispersion forces

B. nylon is a condensation polymer whilst polyethene is an addition polymer

C. nylon has far more crosslinks than polyethene

D. nylon produces a much smoother fibre than polyethene with fewer branches

Q17. In a crosslinked polymer the MAJOR force holding the chains together is due to:

A. covalent bonding

B. ionic bonding

C. hydrogen bonding

D. dispersion forces

Q18. Catalytic cracking is a technique commonly used to generate larger quantities of the more useful compounds from less valuable long-chain hydrocarbons found in petroleum. Two of the most industrially valuable organic molecules produced by this process are:

A. ethene and octane

B. ethyne and hydrogen gas

C. ethanol and ethanoic acid

D. paraffin wax and lip balm

Q19. A polymer used in the manufacture of artificial eyes has the structure shown below:

The monomer/s used in the manufacture of this polymer would be:

A. B.

C. D.

Q20. Butadiene (CH2==CH.CH==CH2) is the major constituent of latex, or natural rubber. Latex does NOT display the elastomeric properties that make modern rubbers so very useful. In order to make latex into an elastomer it must first be:

A. mixed with a plasticiser such as styrene to make it more flexible

B. vulcanised with sulfur to form partial crosslinks

C. oxidised in the presence of UV light to strengthen it

D. reacted with ethene to form a linear polymer

Section B: Extended Answer responses (25 marks)

Q1. Write balanced equations for each of the following reactions:

a) the complete combustion of butane in plentiful oxygen to produce carbon dioxide and water vapour

b) the incomplete combustion of hexyne in a limited supply of oxygen to produce carbon monoxide and water vapour

c) the substitution reaction of methane with chlorine gas (Cl2) in the presence of UV light, which acts as a catalyst for the reaction

d) the addition reaction of propene with water in the presence of an acid catalyst to produce 2-propanol

(8 marks)

Q2. Why are methane and ethane gases at room temperature while octane and decane are liquids?

(2 marks)

Q3. Describe the characteristic/s that a monomer must possess for it to be able to react to form a (an):

(i) addition polymeer

(ii) condensation polymer

(2 marks)

Q4. Draw structural formulae for each of the following:

(i) 2-butene

(ii) pentanoic acid

(iii) 2,2,4-trimethyl-hexane

(iv) 2-chloro-butan-3-ol

(4 marks)

Q4. Name the following structures:

(i)

(ii)

(iii)

(iv)

(4 marks)

Q5. The polymer “polystyrene” is used extensively in a wide range of applications, both in its natural form (as a strong plastic used in model aeroplanes) or in expanded form (as a packaging material for electronic appliances and a filling in “bean bags”).

(i) Draw the structural formula of the monomer that generates this polymer.

(ii) Draw the structural formula of a small section of this polymer.

(iii) Is the reaction to produce this polymer an example of addition polymerisation or condensation polymerisation?

(3 marks)

Q6. Low molecular weight esters are commonly used in food essences and as fragrances in laundry detergents and hair shampoos. Write a full structural equation for the reaction of ethanol with ethanoic acid (glacial acetic acid) to produce such an ester. Name the ester produced and the agent used as a catalyst for this reaction.

(2 marks)

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