# You have a blue gumball that weighs 4.289 g. You soak the gumball in exactly 10.

You have a blue gumball that weighs 4.289 g. You soak the gumball in exactly 10.17 mL of NANOpure™ water (ultrapure water) for 50 seconds at room temperature then remove the gumball, giving you a blue colored aqueous (water) extract. Subsequently you fill a cuvette about ¾ full with this aqueous extract and find a λmaxof 609 nm with an absorbance spectrometer. This corresponds to FD&C Blue Dye #2 (MM = 466.35 g/mol). At the same time you record the absorbance at 609 nm of the aqueous extract as 0.916. The molar bsorptivity ε of FD&C Blue Dye #2 is 2.24 X 104M-1cm-1 at λmax= 609 nm. Determine the mass (in grams) of FD&C Blue Dye #2 per mass of gumball (in grams).Present the complete set of calculations for determining the grams of FD&C Blue #2 per gram of gumball. Remember to symbolically state all equations, defining all variables and constants. (Hint there are four calculations here, one using Beer’s Law to find the dye concentration, and from that another to find the moles of dye, which leads to the third to determine the mass of dye, that leads to the fourth, the desired mass of dye per mass of gumball.)

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