Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
331–335 of 335 · Normal
Question 331
8 marks · Normal
Answer and see the solution →The hydrocarbon octane, C8H18, is a major component of gasoline (petrol). Gasoline is mainly used as a fuel in cars.
(a)[1 mark]State what organic chemistry is the study of.
(b)[1 mark]Name the homologous series to which octane belongs.
(c)[2 marks]Explain how the name 'octane' shows the number of carbon atoms in each molecule, including the code used for the chain length.
(d)[2 marks]Complete the equation for the complete combustion of octane (C8H18). State the formulae of all products.
(e)[2 marks]State one typical use of gasoline and explain why its properties make it suitable for this use.
Question 332
8 marks · Normal
Answer and see the solution →This question is about the structures of alcohols and carboxylic acids.
(a)[2 marks]Draw the displayed formula for propan-1-ol.
(b)[2 marks]Draw the displayed formula for propanoic acid.
(c)[1 mark]Give the molecular formula for butan-1-ol.
(d)[1 mark]How many carbon atoms are in a molecule of methanoic acid?
(e)[2 marks]Explain in one sentence how the name of an alcohol or a carboxylic acid indicates the number of carbon atoms in the molecule.
Question 333
8 marks · Normal
Answer and see the solution →This question is about the IUPAC naming of alcohols and carboxylic acids.
(a)[2 marks]State the IUPAC (systematic) name for the alcohol with structural formula CH3CH(OH)CH3.
(b)[2 marks]Give the IUPAC (systematic) name for the carboxylic acid with the displayed formula:
Displayed formula for CH3CH2COOH (c)[2 marks]Give the name and the correct IUPAC name for the alcohol with the formula CH3CH2CH2CH2OH.
(d)[1 mark]State the name of the main component of vinegar.
(e)[1 mark]Why does propanoic acid not require a number in its IUPAC name, while alcohols such as propanol often do?
Question 334
8 marks · Normal
Answer and see the solution →Ethanol is used as a biofuel and is responsible for the sour taste in vinegar when it is oxidised to ethanoic acid.
(a)[2 marks]Write a balanced symbol equation for the complete combustion of ethanol.
(b)[3 marks]Calculate the mass of water produced when 4.60 g of ethanol ( C2H5OH , Mr = 46) burns completely in excess oxygen.
(c)[2 marks]State the name and formula of the acid formed when ethanol is oxidised and explain briefly why it tastes sour.
(d)[1 mark]On the label of a bottle of vinegar, ethanoic acid is listed as a main ingredient. Is ethanoic acid a strong or weak acid? Explain your answer.
Question 335
8 marks · Normal
Answer and see the solution →This question is about oxidation reactions and the behaviour of carboxylic acids with metals.
(a)[3 marks]Describe how ethanol can be oxidised in the laboratory using potassium dichromate(VI) and dilute sulfuric acid. State what observable change is seen in the reaction mixture.
(b)[3 marks]After oxidation, a sample of the product is added to a test-tube containing magnesium ribbon. Describe two observations you would make and write a balanced symbol equation for the reaction.
(c)[2 marks]Explain why ethanoic acid reacts more slowly with magnesium than hydrochloric acid does.