Question

6. (20 points) A Beer's law curve for a red food dye (max ed food dye (max = 505 nm) is shown Absorbance vs. Concentration of Red Dye Absorbance at 505nm (AU) NO NON y 1.64x R1 -0.9993 0.1 0.2 0.5 0.6 0.7 0.3 0.4 Concentration (M) The red food dye used to prepare the standard solutions for the Beer stay above is also one of the components of Strawberry Kool Aid mix. An unknown mass of Strawberry Kool-Aid mix was dissolved in enough m make exactly 500.00 mL of solution. The absorbance of this solution was determined to be 0.130 AU at a wavelength of 505 nm. a. What is the molar concentration of the red food dye in the Strawberry Kool- Aid solution described above? 0.130 AU = 0 gozantooshan concentrat olanty of the solution 16.64 b. What is the mass of the red food dye in this Strawberry Kool Aid solution? (Given that the molecular weight of the red food dye is 93.2 g/mol)

Answer 1

I can't plot 0.13 on the Graph, from the picture,I could plot it if it would be in my Hand. So, I'm telling you, how you'll solve this problem.

a) First, point 0.13 on the Y-Axis(Absorbance), draw a horizontal line from 0.13 on Y-Axis to the Calibration Curve. Then from the Intersection Point on the Calibration Curve, draw a Vertical Line to the X-Axis (Concentration). Thus, you'll get the Exact Concentration of the Red Food Dye in the Solution, from the Absorbance Value.

b) Now, multiply the Concentration (M) by 93.2, to get the mass of the Dye in the solution.

According to the guess of my eye, the Concentration would be somewhere ~0.6(M)