CAIE A Level Chemistry 9701 · States of matter
A sealed steel cylinder contains nitrogen gas at high pressure.
Explain how the nitrogen gas exerts a pressure on the inside walls of the cylinder.
Nitrogen is sometimes treated as an ideal gas in calculations.
Explain what is meant by an ideal gas.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.