Unit 06 · Kinetics & Equilibrium
Some reactions finish in an instant; others crawl, and many never finish at all but settle into a balance. This unit covers how fast reactions go and why — collision theory, activation energy, catalysts — and what happens when forward and reverse rates equalize: dynamic equilibrium, the equilibrium constant K, and Le Châtelier's principle for predicting how a system shifts under stress. Mastery means you can both speed a reaction up and steer where it settles.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Reaction rate & factors | Cannot name what changes a reaction's speed. | Lists factors but cannot explain why each works. | Predicts and explains how concentration, temperature, surface area, and catalysts change rate. |
| Collision theory & activation energy | Thinks every collision yields a reaction. | Mentions activation energy but not orientation or energy thresholds. | Uses collision theory and energy profiles to explain effective vs. ineffective collisions. |
| Dynamic equilibrium | Believes reactions simply stop at equilibrium. | Says rates are equal but calls the system static. | Describes equilibrium as equal forward and reverse rates with constant concentrations. |
| Le Châtelier's principle & K | Cannot predict the effect of a stress. | Predicts a shift's direction but not its cause or the role of K. | Predicts shifts from changes in concentration, temperature, or pressure and interprets the magnitude of K. |
| Lab technique (rate / equilibrium shift) | Cannot observe or time a rate change. | Collects data but draws conclusions loosely. | Measures a rate or induces a visible equilibrium shift and links the observation to theory. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“Raising the temperature sped the rate up because more collisions clear the activation energy. Then I added product and the equilibrium shifted back toward reactants — Le Châtelier — to relieve the stress I put on it.”
“Hotter just means faster. Equilibrium means both sides are equal amounts, I think.”
You demonstrate this unit through a rate-of-reaction investigation and an equilibrium-shift demonstration — such as a color-changing cobalt or iron-thiocyanate system — explaining each shift aloud, not on a multiple-choice test. A criterion counts as mastered only when you can produce the change at the bench and justify it with theory. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.