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 2 years ago

10 mL sample solution that contains arsenic each is filled into 5 100 mL-volumetric flasks. Then...

10 mL sample solution that contains arsenic each is filled into 5 100 mL-volumetric flasks. Then into the second volumetric flask until the fifth volumetric flask each added 5, 10, 15, and 20 mL standard solution 22.1 ppm of arsenic. Then water is added to all volumetric flasks until the volume reached the 100 mL mark. Then the absorbance of each solution is measured, with the data below. Calculate the content of As in sample. Standard (mL) Absorbance 0.00 0.156...

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Three aliquots of a sample solution containing Ca2+ were analyzed using the procedure given above. The...

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What is the molality of a solution containing 50.6 mL of water (d= 1.00 g/mL) and...

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A solution is made by mixing exactly 500 mL of 0.153 M NaOH with exactly 500...

A solution is made by mixing exactly 500 mL of 0.153 M NaOH with exactly 500 mL of 0.100 MCH3COOH. Calculate the equilibrium concentration of the species below. Ka of CH3COOH is 1.8 ×10−5 [H+]=? M [OH-]=? M [CH3COOH]=? M [Na+]=? M [CH3COO−]=? M

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A solution is made by mixing exactly 500.0 mL of 0.167 M NaOH with exactly 500.0...

A solution is made by mixing exactly 500.0 mL of 0.167 M NaOH with exactly 500.0 mL of 0.100 M CH3COOH. Calculate the equilibrium concentrations of H3O+, CH3COOH, CH3COO-, OH-, and Na+. [H3O+] = M [CH3COOH] = M [CH3COO-] = M [OH-] = M [Na+] = M

2.Calculate the pH of a solution made by mixing 50.00 mL of 0.100 M KCN with...

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What is the pH of a solution made by mixing 500 mL of 1.00 M HCN...

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Be sure to answer all parts. A solution is made by mixing exactly 500 mL of...

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