In the UV-vis spectrum of buta-1,2-diene (CH3CH=c=CH2), the longest-wavelength absorption appears at 178 nm. Compare this to the longest-wavelength absorption in buta-1,3-diene (see Table 15-1) and explain the significant difference. TABLE 15-1 Amax for the Longest-Wavelength UV-Vis Absorptions of a Variety of Organic Compounds Compound Amax (nm) Compound Amax (nm) Compound Amax (nm) Alkanes and <150 cycloalkanes H 161 217 256 Buta-1,3-diene Ethene Cyclohexa-1,3-diene 177 223 274 Hex-1-ene cis-Penta-1,3-diene Hexa-1,3,5-triene 178 223.5 280 Penta-1,4-diene trans-Penta-1,3-diene H H. Methanal (Formaldehyde) 182 224 290 Octa-1,3,5,7-tetraene 2-Methylbuta-1,3-diene (Isoprene) Cyclohexene H.C, 185 239 340 H. Нех-1-yne Cyclopentadiene Propenal (Acrolein) 455 B-Carotene O

In the UV-vis spectrum of buta-1,2-diene (CH3CH=c=CH2), the longest-wavelength absorption appears at 178 nm. Compare this to the longest-wavelength absorption in buta-1,3-diene (see Table 15-1) and explain the significant difference. TABLE 15-1 Amax for the Longest-Wavelength UV-Vis Absorptions of a Variety of Organic Compounds Compound Amax (nm) Compound Amax (nm) Compound Amax (nm) Alkanes and <150 cycloalkanes H 161 217 256 Buta-1,3-diene Ethene Cyclohexa-1,3-diene 177 223 274 Hex-1-ene cis-Penta-1,3-diene Hexa-1,3,5-triene 178 223.5 280 Penta-1,4-diene trans-Penta-1,3-diene H H. Methanal (Formaldehyde) 182 224 290 Octa-1,3,5,7-tetraene 2-Methylbuta-1,3-diene (Isoprene) Cyclohexene H.C, 185 239 340 H. Нех-1-yne Cyclopentadiene Propenal (Acrolein) 455 B-Carotene O

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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