23.Which of the following is o in its most stable conformation? h C D E)All of these are in their most stable conformation. Ans:A 24.What isthe poteial energy changeo fromstbomaion? 45 Kcal/mol Ans:C 25.Which of the following structures represent cis-1,4-dimethyleyclohexane? H CHa A)I&ⅡB)I&llC)Ⅱ&lⅢlD)all of the above E)none of the above Ans:B Page 10 Page 10 23. Which of the following is not in its most stable conformation? A) Cl CH3 B) I CH2CH3 C) H3C OCH3 D) HOOC Br E) All of these are in their most stable conformation. Ans: A 24. What is the potential energy change to convert from a twist-boat to boat conformation? A) –14 Kcal/mol D) 14 Kcal/mol B) 0 Kcal/mol E) 45 Kcal/mol C) 1.4 Kcal/mol Ans: C 25. Which of the following structures represent cis-1,4-dimethylcyclohexane? H CH3 CH3 H I CH3 H CH3 H II CH3 H H H3C III A) I & II B) I & III C) II & III D) all of the above E) none of the above Ans: B