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1.    recall that the relative atomic mass (Ar) of an atom is the mass of the atom compared with that of the carbon-12 isotope, which has a mass of exactly 12, and demonstrate knowledge and understanding that Ar is a weighted mean of the mass numbers ;
2.    calculate the relative formula mass (Mr) (relative molecular mass) of a compound and the percentage of an element, by mass, in a compound;

QUANTITATIVE  CHEM(PART 1)

3. Demonstrate knowledge and understanding that chemical amounts are measured in moles and that the mass of one mole of a substance in grams is numerically equal to the relative formula mass;

4. Convert the given mass of a substance to the amount of the substance in moles (and vice versa) by using the relative atomic or formula mass; 

5. Demonstrate knowledge and understanding of the importance of scale in chemistry in terms of calculating moles from masses given in tonnes and kilograms, for example in industrial processes.


6.    Calculate the reacting masses of reactants or products, given a balanced symbol equation and using moles and simple ratio, including examples where there is a limiting reactant;

7.    Calculate the theoretical yield and the percentage yield of a chemical reaction given the actual yield;

8.    Recognise possible reasons why the percentage yield of a product is less than 100%, including loss of product in separation from the reaction mixture, as a result of side reactions or because the reaction is reversible and may not go to completion;

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9.    demonstrate knowledge and understanding of the terms empirical formula, molecular formula, hydrated, anhydrous and water of crystallisation;

10.    demonstrate knowledge and understanding that water of crystallisation can be removed by heating to constant mass and any thermal decomposition may be carried out to completion by heating to constant mass;

11.    calculate the relative formula mass of compounds containing water of crystallisation;

12.    calculate the percentage of water of crystallisation in a compound;

13.    determine the empirical formulae of simple compounds and determine the moles of water of crystallisation present in a hydrated salt from percentage composition, mass composition or experimental data

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