Question

1. A student makes a solution by mixing 7.0 mL of a 4.5 x 10 M solution of Allura Red and 3.0 ml of water. What is the concentration of Allura Red in the resulting solution? A student is interested in the concentration of blue dve in his favorite beverage. He knows that spectroscopy can be used to determine the concentration of dye molecules in a solution. After making several solutions of known concentration, the student measured the absorbance of each of the solutions and prepared the following calibration curve 2. Blue Dye Calibration Curve 8663 R-0.9998 09 0.8 07 0.6 0.5 0.4 03 0.2 0.1 0.00E 00 2.00E 06 400E-06 600E 06 8.00E-06 1001E 05 1.20E-05 1.40E-05 Dye Concentration (M) The student then finds that if 20.0 mL of his favorite beverage is diluted to a volume of 100.0 ml, the diluted solution has an absorbance of 0.730. Determine the concentration of blue dye in the undiluted beverage. Experiment 1O Report Sheet BE SURE TO ATTACH YOUR CALIBRATION CURVE TO THIS REPORT SHEET!!! 10-7 aueguosg PR22222

Answer 1

in number of moles of solute remains same dilution. number of moles = molarity & volume molarity cong & conc. = molarity X Vidil m, xv, = M₂ X V₂ m, = 4.5 x 100m, v = 7.00 mL m₂ = ? v= 7.00 +3.00 = 10.00mL M = M, X 1 = 4.5*103m xy 10 -3 = 3.15 x 10 m. conc. of diluted solution = 1.06x10 m (from graph) 1.06 x 10 mx 100 ml = mundil x 20ml mundiluted = 5.3 x 10 m