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    Q: The sodium thiosulfate solution was prepared by dissolving 4.5 g of sodium thiosulfate in water and making the solution up to 250 cm^3 in a volumetric flask. The volumetric flask is accurate to 0.3 cm^3 so, to match this accuracy, the mass of the sodium thiosulfate should be accurate to at least

    A. 0.5 g
    B. 0.05 g
    C. 0.005 g
    D. 0.0005 g

    The answer is C. But why??? I have no clue at all

    Please teach me(
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    (Original post by mystreet091234)
    Q: The sodium thiosulfate solution was prepared by dissolving 4.5 g of sodium thiosulfate in water and making the solution up to 250 cm^3 in a volumetric flask. The volumetric flask is accurate to 0.3 cm^3 so, to match this accuracy, the mass of the sodium thiosulfate should be accurate to at least

    A. 0.5 g
    B. 0.05 g
    C. 0.005 g
    D. 0.0005 g

    The answer is C. But why??? I have no clue at all

    Please teach me(
    Calculate the percentage inaccuracy by 100 x 0.3/250

    Now take this percentage of the mass needed.
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    (Original post by charco)
    Calculate the percentage inaccuracy by 100 x 0.3/250

    Now take this percentage of the mass needed.
    To match the accuracy, they should have same percentage uncertainty?
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    (Original post by mystreet091234)
    To match the accuracy, they should have same percentage uncertainty?
    I guess. Although in practical terms this is highly unlikely
 
 
 
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