CH3ċ-OCH3CH;H*4. The UV spectrum of acetone shows absorption maxima at 166, 189, and 279 nm. What type oftransition is responsible for each of these bands? Hint: Consult Table 7.3.*5. Chloromethane has an absorption maximum at 172 nm, bromomethane shows an absorption at204 nm, and iodomethane shows a band at 258 nm. What type of transition is responsible forcach band? How can the trend of absorptions be explained?*6. What types of electronic transitions are possible for each of the following compounds?(a) Cyclopentene(b) Acetaldehyde(c) Dimethyl ether(d) Methyl vinyl ether(e) Triethylamine(f) Cyclohexane7. Predict and explain whether UV/visible spectroscopy can be used to distinguish between thefollowing pairs of compounds. Where possible, support your answers with calculations.CH3CH3CH3CH3CH3CH3CH3CH3CH,-CH3CH3CH3ОНCH2 OHCH3-CH,CH3CH30–CH2-CH3CH3-CH0-CH3End| RecommendedWord Count: 0 PROBLEMS*1. The ultraviolet spectrum of benzonitrile shows a primary absorption band at 224 nm and asecondary band at 271 nm.(a) If a solution of benzonitrile in water, with a concentration of 1 x 104 molar, is examined ata wavelength of 224 nm, the absorbance is determined to be 1.30. The cell length is 1 cm.What is the molar absorptivity of this absorption band?(b) If the same solution is examincd at 271 nm, what will be the absorbance reading(ɛ = 1000)? What will be the intensity ratio, Io/I?*2. Draw structural formulas that are consistent with the following observations.(a) An acid, C7H4O2C12, shows a UV maximum at 242 nm.(b) A ketone, C3H140, shows a UV maximum at 248 nm.(c) An aldehyde, C3H120, absorbs in the UV with Amax = 244 nm.*3. Predict the UV maximum for each of the following substances.(а)(b)CH,=CH--C-CH3CH3CH,– CH3CH3CH3(c)(d)CH3CH3(e)CH3(f)CH3CH3CH;-C-O(h)OCH3C-CH3CH30.CH3(i)(j)CH3:-OCH3CH-C-NH

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*4. The UV spectrum of acetone shows absorption maxima at 166, 189, and 279 nm. What type of transition is responsible for each of these bands? Hint: Consult Table 7.3.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter9: Atomic Absorption And Atomic Fluorescence Spectrometry

Section: Chapter Questions

Problem 9.8QAP

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