Photo AI
Crude oil is separated into different fractions by fractional distillation - Edexcel - GCSE Chemistry - Question 6 - 2016 - Paper 1
Question 6
Crude oil is separated into different fractions by fractional distillation. (a) Fraction X is obtained from near the top of the fractionating column. Fraction Y is o... show full transcript
Worked Solution & Example Answer:Crude oil is separated into different fractions by fractional distillation - Edexcel - GCSE Chemistry - Question 6 - 2016 - Paper 1
Step 1
Fraction X compared with fraction Y - boiling point, ease of ignition and viscosity
Answer
The correct answer is D, which indicates that fraction X has a higher boiling point than Y, easier ignition, and higher viscosity. This is because lower fractions of crude oil (like Y) generally have lower boiling points, ignitability, and viscosity as they contain lighter hydrocarbons, whereas fractions higher up (like X) have properties that show these characteristics.
Step 2
Write the balanced equation for this reaction.
Answer
The balanced chemical equation for the combustion of pentane can be written as:
ightarrow 5CO_2 + 6H_2O$$ This shows that one molecule of pentane reacts with eight molecules of oxygen to produce five molecules of carbon dioxide and six molecules of water.Step 3
Explain how the product of combustion of this impurity in a fuel can damage the environment.
Answer
The combustion of sulfur impurities in fuels produces sulfur dioxide (SO₂), which contributes to air pollution. When sulfur dioxide is released into the atmosphere, it can react with water vapor to form sulfuric acid, leading to acid rain. Acid rain can damage ecosystems, harm aquatic life, and corrode buildings and monuments, posing significant risks to the environment.