Except for sections on Spectroscopy (IR, MS, and NMR), most chapters from the middle of Organic 1 require an understanding of reaction mechanism. Those paths are split into concerted or stepwise, and feature acid-base chemistry, resonance patterns, and outcomes based on steric or electronic factors or both. All of these ideas are introduced in Organic 1 and are used in Organic 2. Weakness in student performance is easily traced to not being solid in those core chapters.