Chemistry

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The dye molecule 7-aminocoumarin has an extinction coefficient of 2800M-1cm-1 at 432nm. An aqueous sample of 7-aminocoumarin is placed in a cuvette with a 1.00cm path length and the absorbance is found to be 1.75 at 432nm. What is the molarity of 7-aminocoumarin in this sample?

  • Chemistry -

    The extinction coefficient is the slope of the line, and will not change ever at 432nm. This is just plug and chug.

    A=ebc
    A=1.75
    e=2800M-1cm-1
    b=1.00cm
    c=?

    solve for c,


    A/be=c

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