2. An analysis for borohydride ion is based on its reaction with Ag+: BH4 - + 8Ag+ + 8OH- -> H2BO3 - + 8Ag(s) + 5H2O The purity of a quantity of KBH4 to be used was established by diluting 3.213 g of the material to exactly 500.0 mL, treating a 100.0-mL aliquot with 50.00 mL of 0.2221 M AgNO3, and titrating the excess silver ion with 3.36 mL of 0.0397 M KSCN. Calculate the percent purity of the KBH4 (53.941 g/mol).

2. An analysis for borohydride ion is based on its reaction with Ag+: BH4 - + 8Ag+ + 8OH- -> H2BO3 - + 8Ag(s) + 5H2O The purity of a quantity of KBH4 to be used was established by diluting 3.213 g of the material to exactly 500.0 mL, treating a 100.0-mL aliquot with 50.00 mL of 0.2221 M AgNO3, and titrating the excess silver ion with 3.36 mL of 0.0397 M KSCN. Calculate the percent purity of the KBH4 (53.941 g/mol).

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.15QAP

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An analysis for borohydride ion is based on its reaction with Ag+: BH4- + 8Ag+ + 8OH- → H2BO3- + 8Ag(s) + 5H2O The purity of a quantity of KBH4 to be used in an organic synthesis was established by diluting 3.258g of the material to exactly 500.0mL, treating a 100.0 mL aliquot with 50.00 mL of 0.2639M AgNO3 and titrating the excess silver ion with 3.36 mL of 0.0397 M KSCN. Calculate the percent purity of the KBH4 [Report the numerical value of the result to two decimal places - NO UNITS]
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