{ "problem_id": "Exam-05-T8", "header": "Problem 8 Basic Organic Chemistry", "header_images": [], "subquestions": [ { "sub_id": "Exam-05-T8-1", "tags": [ "1.2", "1.6" ], "text_open": "8.2 Apply conformational analysis analogous to n-butane. 8.2.1 Rank the shown conformations of 1-butene from high to low energy.", "text_images": [ { "file": "Exam-05-T8-1-1-prompt.png", "description": "3 conformations of C=CCC. A has a left double bond and a zigzag chain ending in an ordinary vertical-up bond. B has a similar skeleton but an upward solid-wedge terminal bond. C has a solid-wedge terminal bond directed lower right." } ], "full_mark": 2, "rubric": [ "B > A > C. (2 points; if n pairwise swaps give the correct order, award 2 - n.)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-2", "tags": [ "1.2", "1.6" ], "text_open": "8.2.2 Rank the shown conformations of allyl alcohol from high to low energy.", "text_images": [ { "file": "Exam-05-T8-2-1-prompt.png", "description": "4 conformations of C=CCO. A ends in an ordinary upward OH bond; B in an upward solid-wedge OH bond; C in a rightward solid-wedge OH bond of different orientation; D ends directly in OH by an ordinary line without wedge stereochemistry." } ], "full_mark": 2, "rubric": [ "D > B > C > A. (2 points; if n pairwise swaps give the correct order, award 2 - n.)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-3", "tags": [ "1.2", "1.6" ], "text_open": "8.2.3 Rank the shown conformations of 2-methyl-1-butene from high to low energy.", "text_images": [ { "file": "Exam-05-T8-3-1-prompt.png", "description": "4 conformations of 'C=C(C)CC'. A has the terminal methyl cis to the double bond by an ordinary upward bond; B has an upward solid wedge; C a lower-right solid wedge; D an ordinary trans arrangement." } ], "full_mark": 2, "rubric": [ "D > B > A > C. (2 points; if n pairwise swaps give the correct order, award 2 - n.)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-4", "tags": [ "1.2", "1.6" ], "text_open": "8.2.4 Rank the shown conformations of methylallyl alcohol from high to low energy.", "text_images": [ { "file": "Exam-05-T8-4-1-prompt.png", "description": "4 conformations of 'C=C(C)CO'. A has OH cis to the double bond by an ordinary line; B an upward solid-wedge OH; C a rightward solid-wedge OH; D an ordinary trans double-bond/OH arrangement." } ], "full_mark": 2, "rubric": [ "D > B > C > A. (2 points; if n pairwise swaps give the correct order, award 2 - n.)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-5", "tags": [ "1.5", "1.6" ], "text_open": "8.3.3 Which has the largest X-C-O bond angle, X = CF_3, CH_3, or CBr_3?", "text_images": [], "full_mark": 1, "rubric": [ "B. (1 point)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-6", "tags": [ "1.6" ], "text_open": "8.3.4 Which of X-C-O (X = CF_3, CH_3, CBr_3) has the smallest bond angle?", "text_images": [], "full_mark": 1, "rubric": [ "A. (1 point)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-7", "tags": [ "1.7" ], "text_open": "8.4 Ring strain can strongly affect reaction rates and equilibria. 8.4.1 Rank the substances from greatest to least ring strain.", "text_images": [ { "file": "Exam-05-T8-7-1-prompt.png", "description": "3 compounds: A, 'C1CC=CC1'; B, 'C1=CC=CC1'; C, 'C=C1CCCC1'." } ], "full_mark": 2, "rubric": [ "A > C > B (2 points). If the order is not completely correct and n swaps are required to obtain the correct order, award 2 - n points, with a minimum score of 0." ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-8", "tags": [ "1.7" ], "text_open": "8.4.2 Select the substance that reacts faster with NaBH_4.", "text_images": [ { "file": "Exam-05-T8-8-1-prompt.png", "description": "2 compounds: A, 'O=C1CCCC1'; B, 'O=C1CCCCC1'." } ], "full_mark": 1, "rubric": [ "B. (1 point)" ], "rubric_images": [] }, { "sub_id": "Exam-05-T8-9", "tags": [ "1.7" ], "text_open": "8.4.3 Select the substance with the greater equilibrium enol fraction.", "text_images": [ { "file": "Exam-05-T8-9-1-prompt.png", "description": "2 compounds: A, 'O=C1C(C(OCC)=O)CCC1'; B, 'O=C1C(C(OCC)=O)CCCC1'." } ], "full_mark": 1, "rubric": [ "B. (1 point)" ], "rubric_images": [] } ] }