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49.9 ml of a 0.00292 m stock solution of a certain dye is ddiluted to 1.00 L. the diluted solution has an absorbance of 0.600. what is the molar

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Complete Question

49.9 ml of a 0.00292 m stock solution of a certain dye is diluted to 1.00 L. the diluted solution has an absorbance of 0.600. what is the molar absorptivity coefficient of the dye

Answer:

The  value is  [tex]\epsilon = 4118.1 \ M^{-1} cm^{-1}[/tex]  

Explanation:

From the question we are told that

   The volume of the stock solution is  [tex]V_1 = 49.9 mL = 0.0499 \ L[/tex]  

   The concentration of the stock solution is  [tex]C_1 = 0.00292 \ M[/tex]

   The volume of the diluted solution is  [tex]V_2 = 1.00 \ L[/tex]

   The absorbance is  [tex]A = 0.600[/tex]

Generally the from the titration equation we have that

         [tex]C_1 * V_1 = C_2 * V_2[/tex]

=>      [tex]0.00292 * 0.0499 = C_2 * 1[/tex]

=>     [tex]C_2 = 0.0001457 \ M[/tex]

Generally from  Beer's law we have that

      [tex]A = \epsilon * l * C_2[/tex]

=>   [tex]\epsilon = \frac{A}{ l * C_2 }[/tex]

Here  l is the length who value is  1 cm because the unit of  molar  absorptivity coefficient of the dye is [tex]M^{-1} * cm^{-1}[/tex]

So

            [tex]\epsilon = \frac{0.600}{ 1 * 0.0001457 }[/tex]  

=>       [tex]\epsilon = 4118.1 \ M^{-1} cm^{-1}[/tex]