What you’ll learn3 learning objectivesChoose one objective for a focused lesson, or study the complete topic.3.2.1Relative atomic mass, Ar, as the• Describe relative atomic mass, Ar, as the average mass of the isotopes of an element compared to 1/12th of the mass of an atom of 12CSyllabus objective3.2.2Relative molecular mass, Mr, as the• Define relative molecular mass, Mr, as the sum of the relative atomic masses. Relative formula mass, Mr, will be used for ionic compoundsSyllabus objective3.2.3Reacting masses in simple proportions• Calculate reacting masses in simple proportions. Calculations will not involve the mole conceptSyllabus objective