Explain4 marksStandard
Propane has the molecular formula .
Explain, in terms of the Avogadro constant, what is meant by one mole of propane molecules and what this amount of propane tells you about the amounts of carbon and hydrogen atoms present.
CAIE A Level Chemistry 9701 · Atoms, molecules and stoichiometry
Atoms, molecules and stoichiometry: explain question
How this question is marked
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.
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