Reactions Rates
Start with the big picture
A reaction rate measures concentration change per unit time. Rate laws relate the rate to reactant concentrations through a rate constant and experimentally determined reaction orders; those orders also determine the overall order and influence the units of the rate constant. Mechanistic analysis considers elementary steps, molecularity, and the slow, rate-determining step. Integrated rate laws describe concentration–time relationships and half-life behavior. Temperature dependence is treated through the Arrhenius relationship, while collision and transition-state theories explain how successful encounters and activated complexes relate to reaction progress. The lesson also covers how catalysts and factors such as concentration, gas pressure, surface area, agitation, ionic strength, and solvent polarity can affect rates, including pseudo-first-order kinetics.
What you'll learn
- Define reaction rate and interpret a general rate law.
- Distinguish reaction order and molecularity, and relate both to reaction mechanisms.
- Describe how integrated rate laws connect concentration, time, and half-life.
- Explain temperature effects on the rate constant using the Arrhenius equation.
- Identify how catalysts and physical or solution conditions influence reaction rates.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
