O level Chemistry Fuels & Crude Oil (10 qns)

In the fractional distillation of crude oil, bitumen is collected at the bottom of the fractionating column. This is because

• it is the first substance to condense from a gas to a liquid in the column

• it was never vapourised in the heating chamber

• bitumen is a substance that has little or no commercial value

• bitumen is not flammable

Which statement about the fractional distillation of petroleum is correct?

• At each level, only one compound is collected

• The higher up the column, the greater the temperature

• The molecules collected at the bottom of the column are the least flammable

• The molucules reaching the top of the column have the highest velocity

Which statement about hydrogen as a fuel is correct?

• Hydrogen can be obtained by fractional distillation of crude oil

• Hydrogen is the main component found in natural gas

• Hydrogen is a fuel that is easily transported and stored

• Hydrogen reacts with oxygen to produce energy and water

Which statement applies to all three of the compounds ethane, ethene and ethanol

• One mole of each compound contains the same number of hydrogen atoms

• One molecules of each compound contains the same number of carbon atoms

• They are obtained from crude oil

• They are all liquids at room temperature

Which correctly matches the crude oil fraction to its use?

• fraction: bitumen

  use: chemical feedstock

• fraction: diesel

  use: paving road surfaces

• fraction: naphtha

  use: fuel for cooking

• fraction: paraffin

  use: aircraft fuel

A molecule of C₁₇H₃₆ undergoes catalytic cracking. THe products of the reaction are one butane molecule, one propene molecule and some ethene molecules. How many ethene molecules are produced during the reaction?

• 3

• 5

• 6

• 8

Which of the following statements best describes the mechanism of a hydrogen-oxygen fuel cell?

• Hydrogen and oxygen undergo redox reaction to generate electricity

• Hydrogen ions react with hydroxide ions to generate electricity

• Electricity is used to provide heat energy

• Electricity is used to generate hydrogen and oxygen

Which statement(s) best explains why bitumen has a higher boiling point than paraffin?

• Bitumen is more reactive than paraffin

• Bitumen is a pure substance whereas paraffin is a mixture

• Forces of attraction between the molecules of paraffin are weaker than that between the molecules of bitumen

• There are smaller molecules in bitumen compared to the molecules in paraffin

Which compound is the most viscous and the least flammable?

• C₆H₁₄

• C₈H₁₈

• C₁₀H₂₂

• C₁₂H₂₆

Which of the following is true about kerosene?

• Kerosene has a lower viscosity than petrol

• Molecules of kerosene are larger than those in naphtha

• Molecules in kerosene are used to make petrochemicals

• Molecules of kerosene burn with a smoker flame than those in diesel