The revision is based upon the concepts covered on the worksheets:
Relative Molecular Mass (Calculations) (https://www.teacherspayteachers.com/Product/Relative-Molecular-Mass-calculation-860192)
Moles and Mass (https://www.teacherspayteachers.com/Product/Moles-Mass-1876584)
Molar Ratios (https://www.teacherspayteachers.com/Product/Molar-Ratios-1876587)
Yo may find it useful to have used these with your class prior to giving them this homework.
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