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    Can someone help (not asking to do it) me with this problem?
    Thank you.

    Problem:
    You weigh out a piece of copper wire:

    Weight of copper standard 0.3535 g

    Dissolve it in a slight excess of concentrated nitric acid. Add to the solution the required amount of concentrated ammonia. Transfer this quantitatively to a 100 mL volumetric flask, dilute to volume, and mix thoroughly. 10.00 mL of this is pipetted into a 100 mL volumetric flask, the required amount of concentrated ammonia is added and diluted to volume. This is standard 1.
    Standard 2 is made by pipetting 20 mL of the original solution into a 100 mL volumetric flask, adding the required amount of ammonia, and diluting to volume.
    Using the same cuvet for all measurements, the following %T's were obtained:

    Blank 100.7 %
    Standard 1 59.1 %
    Standard 2 32.9 %

    Finally:
    10 mL of unknown was pipetted into a 100 mL volumetric flask. The required amount of ammonia was added and the mixture diluted to volume. The %T of this solution was measured using the same spectrometer and cuvet as for the standards.

    %T unknown 27.7 %

    Calculate:

    a) The absorbance of standard 1 ______________
    b) The absorbance of standard 2 ______________
    c) The molarity of Cu in Standard 1 ______________ M
    d) The molarity of Cu in Standard 2 ______________ M
    e) Ratio: absorbance/molarity std 1 ______________
    f) Ratio: absorbance/molarity std 2 ______________
    g) Average ratio of absorbance/molarity ______________
    h) Absorbance of unknown solution ______________
    Concentration of copper in unknown...
    i) solution as measured in cuvet ______________ M
    j) in original solution ______________ M
    k) in original solution ______________ w/V%
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