quantitative chemistry Flashcards
Calculate relative formula mass given relative atomic masses
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Calculate the formulae of simple compounds from reacting
masses and understand that these are empirical formulae
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Determine the empirical formula of a simple compound, such as magnesium oxide
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Calculate the percentage composition by mass of a compound from its formula and the relative atomic masses of its constituent elements
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Use balanced equations to calculate masses of reactants
and products
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Recall that the yield of a reaction is the mass of product obtained in the reaction
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Demonstrate an understanding that the actual yield of a reaction is usually less than the yield calculated using the chemical equation (theoretical yield)
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Calculate the percentage yield of a reaction from the actual yield and the theoretical yield
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Demonstrate an understanding of the reasons why reactions do
not give the theoretical yield due to factors, including:
a incomplete reactions
b practical losses during the preparation
c competing, unwanted reactions
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Demonstrate an understanding that many reactions produce waste products which:
a are not commercially useful
b can present economic, environmental and social problems for disposal
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Demonstrate an understanding that chemists in industry
work to find the economically most favourable reactions where
a the percentage yield is high
b all the products of the reaction are commercially useful
c the reaction occurs at a suitable speed
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