The concentration of caffeine in an energy soft drink was determined by standard addition using HPLC. The following procedure was used: a standard caffeine solution was prepared by adding 0.09850g of caffeine to 25.0 cm3 of water.A series of solutions were prepared by adding known volumes of the standard solution to the soft drink before diluting to 100 cm3. The volume of standard and the caffeine peak area are shown in the table: Energy Drink (cm3) Added caffeine Std (cm3) Peak area 15 0 965 15 5 1352 15 10 1739 15 15 2126 15 20 25

The concentration of caffeine in an energy soft drink was determined by standard addition using HPLC. The following procedure was used: a standard caffeine solution was prepared by adding 0.09850g of caffeine to 25.0 cm3 of water.A series of solutions were prepared by adding known volumes of the standard solution to the soft drink before diluting to 100 cm3. The volume of standard and the caffeine peak area are shown in the table: Energy Drink (cm3) Added caffeine Std (cm3) Peak area 15 0 965 15 5 1352 15 10 1739 15 15 2126 15 20 25

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter7: Statistical Data Treatment And Evaluation

Section: Chapter Questions

Problem 7.13QAP

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