CAIE A Level Chemistry 9701 · Atoms, molecules and stoichiometry
Sodium chloride is an ionic solid. Natural chlorine is a mixture of and atoms.
(a) Describe what is meant by the unified atomic mass unit.
(b) Describe what is meant by the relative atomic mass of chlorine.
(c) Describe what is meant by the relative formula mass of sodium chloride.
(d) Describe why the relative mass of sodium chloride is called a relative formula mass rather than a relative molecular mass.
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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