The chief chemist of Victory Vinegar Works, Ltd., inter- views two chemists for employment. He states, “Qual- ity control requires that our high-grade vinegar contain 5.00 ± 0.01% acetic acid by mass. How would you analyze our product to ensure that it meets this specification?" Anne Dalton says, "I would titrate a 50.00-11L sample of the vinegar with 1.000 M NaOH, using phe- nolphthalein to detect the equivalence point to within ±0.02 mL of base." Charlie Cannizzarro says, "I would use a pH meter to determine the pH to ±0.01 pH units and interface it with a computer to print out the mass percentage of acetic acid." Which candidate did the chief chemist hire? Why?

The chief chemist of Victory Vinegar Works, Ltd., inter- views two chemists for employment. He states, “Qual- ity control requires that our high-grade vinegar contain 5.00 ± 0.01% acetic acid by mass. How would you analyze our product to ensure that it meets this specification?" Anne Dalton says, "I would titrate a 50.00-11L sample of the vinegar with 1.000 M NaOH, using phe- nolphthalein to detect the equivalence point to within ±0.02 mL of base." Charlie Cannizzarro says, "I would use a pH meter to determine the pH to ±0.01 pH units and interface it with a computer to print out the mass percentage of acetic acid." Which candidate did the chief chemist hire? Why?

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter15: Equilibria Of Other Reaction Classes

Section: Chapter Questions

Problem 11E: The Handbook of Chemistry and Physics (http://openstaxcollege.org/l/16Handbook) gives solubilities...

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The Handbook of Chemistry and Physics (http://openstaxcollege.org/l/16Handbook) gives solubilities of the following compounds in grams per 100 mL of water. Because these compounds are only slightly soluble, assume that the volume does not change on dissolution and calculate the solubility product for each. (a) BaSeO4, 0.0118 g/100 mL. (b) Ba(BrO3)2H2O, 0.30 g/100 mL. (c) NH4MgAsO46H2O, 0.033 g/100 mL. (d) La2(MoO4)3, 0.00179 g/100 mL
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