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Problem 1. 3 peaks (8 C) means considerable symmetry peak at 83 ppm is likely C bonded to O. HRMS gives a mass of 130.1358 which corresponds to C8H18O. IR shows peaks at 2900 and 1060 cm-1. IR indicates only C-O stretch at 1060 cm -1. Problem 2. 6 peaks (6 C) means no symmetry
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Problem 1 3 peaks (8 C) means considerable symmetry peak at 83 ppm is likely C bonded to O HRMS gives a mass of 130.1358 which corresponds to C8H18O. IR shows peaks at 2900 and 1060 cm-1. IR indicates only C-O stretch at 1060 cm-1
Problem 2 6 peaks (6 C) means no symmetry peak at 208 ppm is likely C double bonded to O HRMS gives a mass of 100.0888 which corresponds to C6H12O. IR shows peaks at 2900 and 1710 cm-1. IR indicates only C=O stretch at 1710 cm-1
Problem 3 5 peaks (5 C) means no symmetry peaks at 125 and 132 ppm are likely alkene C’s HRMS gives a mass of 86.0732 which corresponds to C5H10O. IR shows peaks at 3300, 3100, 2900, 1640 and 1060 cm-1. IR indicates C-O stretch at 1060 cm-1 C=C stretch at 1640 cm-1 sp2C-H stretch at 3100 cm-1 O-H stretch at 3300 cm-1
Problem 4 5 peaks (5 C) means no symmetry peaks at 111 and 142 ppm are likely alkene C’s HRMS gives a mass of 70.0783 which corresponds to C5H10. IR shows peaks at 3110, 2900 and 1640 cm-1. IR indicates C=C stretch at 1640 cm-1 sp2C-H stretch at 3110 cm-1
Problem 5 6 peaks (6 C) means no symmetry peaks at 138 and 162 ppm are likely alkene C’s Peak at 201 ppm is the carbonyl C HRMS gives a mass of 98.0732 which corresponds to C6H10O. IR shows peaks at 3100, 2900, 2820, 2720, 1700 and 1610 cm-1. IR indicates C=C stretch at 1640 cm-1 C=0 stretch at 1700 cm-1 sp2C-H stretch at 3100 cm-1
Problem 6 Note that “b” is a singlet, not a triplet because identical hydrogens do not couple 4 peaks (8 C) means the molecule is bisected by a mirror plane Peak at 173 ppm is the carbonyl C Peak at 61ppm is the C bonded to O HRMS gives a mass of 174.0892 which corresponds to C8H14O4. IR shows peaks at 2900, 1720 and 1060 cm-1. IR indicates C-O stretch at 1060 cm-1 C=0 stretch at 1720 cm-1
Problem 7 Three distinct aromatic singlets indicates a 1,3,5-substitution pattern of hydrogens (would couple otherwise) 11 peaks (11C) means no symmetry Many peaks (6) between 120 and 140 ppm indicate a benzene Peak at 166 ppm is the carbonyl C Peak at 52 ppm is C bonded to O HRMS gives a mass of 178.0994 which corresponds to C11H14O2. IR shows peaks at 3100, 2900, 1710, 1600, 1500 and 1060 cm-1. IR indicates C-O stretch at 1060 cm-1 C=C stretches at 1500 and 1600 cm-1 C=0 stretch at 1710 cm-1 sp2C-H stretch at 3100cm-1