Consider the graph below, which is a plot of the relative energies of the various conformations of 2,3-dimethylbutane, viewed through the C2-C3 bond. The conformations corresponding to the angles 120° and 240° are: Relative energy 0° 60° 120° 180° 240° 300° 360° Angle of rotation A. eclipsed (one Me-Me and two Me-H eclipsed) B. eclipsed (one H-H and two Me-Me eclipsed) C. gauche D. anti-periplanar E. none of the above Enter Your Answer: A OB OC OD OE Using the same graph and answer choices from question 9, which conformations correspond to the angles 60° and 300⁰? Enter Your Answer: A OB O C OE

Consider the graph below, which is a plot of the relative energies of the various conformations of 2,3-dimethylbutane, viewed through the C2-C3 bond. The conformations corresponding to the angles 120° and 240° are: Relative energy 0° 60° 120° 180° 240° 300° 360° Angle of rotation A. eclipsed (one Me-Me and two Me-H eclipsed) B. eclipsed (one H-H and two Me-Me eclipsed) C. gauche D. anti-periplanar E. none of the above Enter Your Answer: A OB OC OD OE Using the same graph and answer choices from question 9, which conformations correspond to the angles 60° and 300⁰? Enter Your Answer: A OB O C OE

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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Draw a perspective representation of the most stable conformation of 3-methylhexane. Draw the molecule on the canvas by choosing buttons from the Tools (for bonds and charges), Atoms, and Templates toolbars. 0 + 7 C Akri C H 12D EXP CONT Marvin JS by ChemAxon 1 H CI P UNOS J
3.) 2-Methylbutane (isopentane) is used, in conjunction with liquid nitrogen, to freeze tissues for cryosectioning in histology. Below is the potential energy diagram for all the conformers of 2-methylbutane. Provide structures that match structure A, B, and C in the boxes provided. B F IM C A potential energy Conformer A 0° D angle of internal rotation Conformer B E F H 360° (=0°) Conformer C
a. Use strain energy increments in the OWL Table Reference (see References button, Strain Energy Increments) to calculate the energy difference between the two chair conformations of the compound b. Specify substituent positions (axial or equatorial) in the more stable chair. c. Estimate the percent of the more stable chair at equilibrium at 25°C. (To determine the percent of the more stable chair at equilibrium, first calculate Keq, and then use this value to find the percentage.) CH3 CH3 Answers: a. The energy difference is b. In the more stable chair: • The phenyl group is in the • The isopropyl group is in the | kJ/mol. position. position. c. At 25°C the equilibrium percent of the more stable chair conformation is approximately [
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