ACS CP Cheat Sheet 2026

The 30 highest-yield ACS CP facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which organometallic reaction type involves insertion of an alkene into a metal-hydrogen bond? → Migratory insertion
2. Which analytical technique is most commonly used for measuring trace metal concentrations in environmental water samples? → Inductively coupled plasma mass spectrometry (ICP-MS)
3. In mass spectrometry, what is the base peak? → The most abundant ion in the spectrum
4. In inductively coupled plasma mass spectrometry (ICP-MS), the primary function of the collision/reaction cell is to: → Reduce polyatomic interferences by reacting them with a cell gas
5. Which of the following best describes 'responsible care' as it applies to ACS professional standards? → A voluntary commitment to safely manage chemicals throughout their lifecycle
6. Which process describes the increase in concentration of a persistent pollutant at each successive trophic level in a food chain? → Biomagnification
7. In the Born-Haber cycle for NaCl, which step involves the largest energy release? → Lattice energy formation
8. Which of the following correctly expresses the Gibbs-Helmholtz relationship at constant pressure? → ΔG = ΔH - TΔS
9. Which of the following best promotes ethical collaboration? → Properly crediting contributors
10. When transporting hazardous chemicals on public roads, US regulations require which document to accompany the shipment? → Shipping papers with proper DOT hazard class information
11. In atomic absorption spectroscopy (AAS), what is measured? → Absorption of light by atoms
12. Which experimental technique determines the order of a reaction with respect to individual reactants? → Method of initial rates
13. The Clausius-Clapeyron equation relates vapor pressure to temperature. What does the slope of ln(P) vs 1/T represent? → -ΔHvap/R
14. The Eyring equation from transition state theory expresses the rate constant in terms of: → The enthalpy of activation ΔH‡ and entropy of activation ΔS‡
15. Which spectroscopic method relies on the Raman scattering effect to provide complementary vibrational information to IR spectroscopy? → Raman spectroscopy
16. In collision theory, the Boltzmann factor e^(-Ea/kBT) in the rate constant expression represents: → The fraction of molecular collisions possessing energy ≥ Ea
17. Which technique separates components of a mixture based on boiling points? → Distillation
18. Under the OSHA Hazard Communication Standard (HazCom 2012), which section of a Safety Data Sheet (SDS) contains first-aid measures? → Section 4
19. The Ostwald process for nitric acid production involves catalytic oxidation of ammonia over which catalyst? → Platinum-rhodium gauze
20. Living polymerization techniques (ATRP, RAFT, NMP) are valued in polymer chemistry primarily because they allow: → Precise control of molecular weight, narrow PDI, and synthesis of block copolymers
21. In NMR spectroscopy, a proton that is shielded by electron density will resonate at: → Higher field (lower δ ppm)
22. The hierarchy of hazard controls, in order from most to least effective, begins with: → Elimination of the hazard
23. The GHS (Globally Harmonized System) hazard communication standard uses how many signal words on labels? → One (either 'Danger' or 'Warning')
24. Circular dichroism (CD) spectroscopy is particularly useful for characterizing: → Secondary structure content (alpha-helix, beta-sheet) of proteins in solution
25. For a mechanism with a fast pre-equilibrium step (K₁) followed by a slow rate-determining step (k₂), the observed rate law: → May include concentrations from the pre-equilibrium step via K₁
26. Which federal regulation requires facilities to report releases of extremely hazardous substances above a reportable quantity to local emergency planners? → EPCRA Section 304
27. What is the oxidation state of chromium in K₂Cr₂O₇? → +6
28. Which element is common to all organic compounds? → Carbon
29. For a second-order reaction, the half-life expression is t₁/₂ = 1/(k[A]₀). What happens to the half-life if the initial concentration is doubled? → It is halved
30. Which polymer property describes the distribution of molecular weights in a polymer sample? → Polydispersity index (PDI)