0.3872g of an unknown weak acid with general formula HY, was dissolved in water and made up to a 500mL in a volumetric flask. The measured pH of the solution was 3.90. In a separate titration experiment, the K₂ of HY was determined as 100 x 10-6. The unknown acid HY underwent a series of chemical analyses to determine its structure. An infra-red spectrum of HY showed two main absorption peaks: a strong, sharp absorption at 1700 cm-¹ and a very strong, broad absorption from approximately 2700 - 3400 cm-¹. When reacted with a strong reducing agent, HY formed compound X. Compound X was then mixed with acidified potassium dichromate, producing an orange solution. When it was heated strongly, the solution turned green. A mass spectrum of HY contained two major fragments with m/z values of 43 & 45, respectively. b) Use all the information give above to deduce the most reasonable chemical structures for HY and X; and give the IUPAC names of both compounds. Credit will be awarded for correct reasoning.

0.3872g of an unknown weak acid with general formula HY, was dissolved in water and made up to a 500mL in a volumetric flask. The measured pH of the solution was 3.90. In a separate titration experiment, the K₂ of HY was determined as 100 x 10-6. The unknown acid HY underwent a series of chemical analyses to determine its structure. An infra-red spectrum of HY showed two main absorption peaks: a strong, sharp absorption at 1700 cm-¹ and a very strong, broad absorption from approximately 2700 - 3400 cm-¹. When reacted with a strong reducing agent, HY formed compound X. Compound X was then mixed with acidified potassium dichromate, producing an orange solution. When it was heated strongly, the solution turned green. A mass spectrum of HY contained two major fragments with m/z values of 43 & 45, respectively. b) Use all the information give above to deduce the most reasonable chemical structures for HY and X; and give the IUPAC names of both compounds. Credit will be awarded for correct reasoning.

Chemistry & Chemical Reactivity

9th Edition

ISBN:9781133949640

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter16: Principles Of Chemical Reactivity: The Chemistry Of Acids And Bases

Section: Chapter Questions

Problem 110IL

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