Exactly 1.00-mL aliquots of a solution containing phenobarbital were measured into 50.00-mL volumetric flasks and made...

Exactly 1.00-mL aliquots of a solution containing phenobarbital were measured into 50.00-mL volumetric flasks and made basic with KOH. The following volumes of a standard solution of phenobarbital containing 25 ppm of phenobarbital were then introduced into each flask and the mixture was diluted to volume: 0.00, 1.00, 2.00, 3.00, and 4.00 mL. The fluorescence of each of these solutions was measured with a fluorometer, which gave values of 33.6, 40.6, 47.6, 54.6, and 61.6, respectively. What is the concentration (in ppm) of phenobarbital in the unknown?

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queen_honey_blossom answered 1 year ago

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