Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
321–330 of 335 · Normal
Question 321
2 marks · Normal
Answer and see the solution →Describe how polylactic acid (PLA) is produced from its monomer, lactic acid.
Question 322
4 marks · Normal
Answer and see the solution →Polyesters are condensation polymers that are more biodegradable than many addition polymers.
(a)[1 mark]State what is meant by a condensation polymerisation reaction.
(b)[3 marks]With reference to chemical bonding, explain why polyesters can be biodegraded more easily than addition polymers.
Question 323
3 marks · Normal
Answer and see the solution →Lactic acid has the formula . When making a biodegradable polyester such as polylactic acid (PLA), lactic acid monomers react with each other to form a long polymer chain.
Explain, using your knowledge of its structure, how lactic acid can form a biodegradable polyester like PLA from a single type of monomer.
Question 324
6 marks · Normal
Answer and see the solution →Addition polymers and condensation polymers such as polyesters are used widely in packaging and fabrics. Answer the following questions about these materials.
(a)[1 mark]State what makes addition polymers, such as poly(ethene), difficult to dispose of in the environment.
(b)[2 marks]Landfill and incineration are two ways of disposing of addition polymers. Give one advantage and one disadvantage of using landfill compared to incineration.
(c)[2 marks]Describe briefly how a polyester is made by condensation polymerisation.
(d)[1 mark]Suggest one advantage in terms of disposal if more consumer products were made using polyesters instead of addition polymers.
Question 325
6 marks · Normal
Answer and see the solution →The use and disposal of polymers is an important topic in chemistry. Answer the following structured questions.
(a)[1 mark]State the two main methods used to dispose of addition polymers.
(b)[2 marks]Explain why addition polymers, such as poly(propene), persist in the environment for a long time.
(c)[2 marks]Complete the word equation for the formation of a polyester by condensation polymerisation:
(d)[1 mark]Suggest one environmental benefit of using condensation polymers, like some polyesters, over addition polymers.
Question 326
6 marks · Normal
Answer and see the solution →A company makes 1200 kg of polyester each day by condensation polymerisation, starting from a diol and a dicarboxylic acid. Poly(ethene), an addition polymer, is also made in the same factory.
(a)[1 mark]During polyester formation, a small molecule is eliminated in the reaction. Name this small molecule.
(b)[3 marks]Calculate the total mass of this eliminated small molecule if 1200 kg of polyester is produced and the elimination forms 19% of the total mass of products. Give your answer to the nearest kg.
(c)[2 marks]Addition polymers do not eliminate any small molecule in their formation. Suggest how this difference affects the disposal of polyesters compared to addition polymers.
Question 327
6 marks · Normal
Answer and see the solution →Read the text and answer the questions that follow.
A city council is deciding whether to promote the use of polyesters in place of traditional addition polymers for packaging. They want to consider both environmental impact and chemical properties.
(a)[2 marks]Explain why many addition polymers are considered non-biodegradable.
(b)[2 marks]Describe the process by which polyesters are formed and how this is different from addition polymerisation.
(c)[2 marks]Suggest and explain one environmental benefit of using some polyesters instead of addition polymers for products that may be discarded into the environment.
Question 328
8 marks · Normal
Answer and see the solution →The displayed formulae of simple hydrocarbons can be used to understand their properties and uses.
(a)[2 marks]Draw the displayed formula for but-1-ene.
(b)[2 marks]State the typical number of bonds formed by: (i) carbon (ii) hydrogen (iii) oxygen (iv) chlorine
(c)[2 marks]Fractional distillation of crude oil separates hydrocarbon molecules by their size. Explain why refinery gases rise to the top of the column while bitumen is collected at the bottom.
(d)[2 marks]State one common use for (i) refinery gas and (ii) bitumen.
Question 329
8 marks · Normal
Answer and see the solution →The table below shows properties and displayed formulae for four organic compounds (A, B, C, D).
(a)Table 1: Displayed formulae and boiling points of compounds Compound Displayed Formula Boiling Point (°C) A H–C–C–H (each C with 2 H, straight chain) -161 B H H | | H–C–C–C–H | | H H (each C with correct H count) -42 C H H | | H–C=C–H | | H H -104 D H H | | H–C–C–O–H | | H H 78 Use the table to answer the questions below.
(i)[1 mark]State the type of molecule represented by compound A. How many carbon and hydrogen atoms are in one molecule?
(ii)[2 marks]Identify the compound that belongs to the alcohol homologous series. Give one feature from the displayed formula that confirms this.
(iii)[2 marks]For compound B, describe its molecular structure using the displayed formula. How many single covalent bonds are present?
(iv)[3 marks]Crude oil is separated into fractions by fractional distillation. Based on the boiling points in the table, which compound would be collected at the top of the fractionating column and which at the bottom? Explain your reasoning.
Question 330
8 marks · Normal
Answer and see the solution →Answer all parts.
(a)[2 marks]Give the IUPAC name for the compound with the displayed formula:
Displayed formula: (straight chain) (b)[1 mark]Refinery gases are produced during the separation of crude oil. Name one typical use of refinery gases.
(c)[2 marks]The compound below has a side chain. Use IUPAC conventions to name it.
Displayed formula (side chain on third carbon): (d)[3 marks]Refinery gases, gasoline and other fractions are obtained from crude oil by a particular process. Name this process and briefly describe how compounds are separated during it.