Organic Chemistry ACS Exam (2026/2027) | Exam Questions | Prep Guide | A+

Organic Chemistry ACS Exam (2026/2027)
| Exam Questions | Prep Guide | A+
• 1680 cm-1 (IR) -✓✓amide, C=O stretch


• 1710 cm-1 (IR) -✓✓ketone, C=O stretch


• 1710 cm-1 (IR) -✓✓acid, C=O stretch


• 1725 cm-1 (IR) -✓✓aldehyde, C=O stretch


• 1735 cm-1 (IR) -✓✓ester, C=O stretch


• centered 3000 cm-1 (IR) -✓✓acid, O-H stretch


• centered 3300 cm-1 (IR) -✓✓alcohol, O-H stretch


• 3100-3300 cm-1 (IR) -✓✓amide/amine, N-H stretch, NHn where n=#
of peaks


• 2710 & 2810 cm-1 (IR) -✓✓aldehyde, C-H stretch


• 1660 cm-1 (IR) -✓✓alkene, C=C stretch

, • <2200 cm-1 (IR) -✓✓alkyne, C triple-bond C stretch


• >2200 cm-1 (IR) -✓✓nitrile, C triple-bond N stretch


• M+2 and M+ same size (Mass Spec) -✓✓bromine


• M+2 a third as large as M+ (Mass Spec) -✓✓chlorine


• 127, large gap (Mass Spec) -✓✓Iodine


• odd M+, some even fragments (Mass Spec) -✓✓Nitrogen


• M+2 larger than usual; 4% of M+ (Mass Spec) -✓✓sulfur


• ~7.2 ppm (HNMR) -✓✓aromatic hydrogens, Ph-H


• ~0.9 ppm (HNMR) -✓✓alkane, CH3


• ~1.7 ppm (HNMR) -✓✓allylic, C=C-CH3


• ~1.3 ppm (HNMR) -✓✓alkane, CH2