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    | • | Chemistry is a
    quantitative science based on 
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    |  | experimentation.
    Take measurements. 
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    | • | A measurement is a number and a unit that 
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    |  | describes what
    the measurement is 
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    |  | measuring. 
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    | • | In chemistry we
    use the metric system for 
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    |  | taking
    measurements. We also use scientific 
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    |  | notation to make life easier. 
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