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Beer’s Law Calculations

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    291733
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    Name: _________________________

    1. If you double the wavenumber, you _____________ the energy.

     

    1. If you double the wavelength, you ______________ the energy.

     

    1. How do transmittance, absorbance, and molar absorptivity differ? Which one is proportional to concentration?

     

     

     

     

     

     

     

     

    1. A compound with molecular mass 292.16 g/mol was dissolved in a 5.00 mL volumetric flask. A 1.00 mL aliquot was withdrawn, placed in a 10.00 mL volumetric flask, and diluted to the mark. The absorbance at 340 nm was 0.427 in a 1.000 cm cuvet. The molar absorptivity at 340 nm is ε340 = 6130 M-1*cm-1.
      1. Calculate the concentration of the compound in the cuvet.
      2. What was the concentration of the compound in the 5 mL flask?
      3. How many mg of compound were used to make the 5 mL solution?

         

         

         

         

         







         

    1. Using the molar absorptivity data below, find the [x] and the [y] in a solution whose absorbance is 0.233 at 272 nm and 0.200 at 327 nm in a 0.100 cm cell.
       

      ε (M-1cm-1)

      λ (nm)

      X

      Y

      272

      16,400

      3,870

      327

      3,990

      6,420

       






       

     

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