Kinetics

Reaction Rate

the change in concentration of reactants or products per unit time

Collision Theory

for a chemical reaction to occur, reactant particles must collide with sufficient energy (activation energy) and the correct orientation

Reaction Mechanism

a step-by-step description of how a chemical reaction occurs, from reactants to products

Catalyst

a substance that speeds up a chemical reaction without being consumed itself, by providing an alternative reaction pathway with a lower activation energy

Enthalpy

a measure of the total heat content of a system (ΔH)

Entropy

• a measure of the disorder of a system

  • Gases have the most entropy; Solids have the least entropy

  • Nature trends towards low energy and high entropy

Potential Energy Diagrams

 a visual representation of the energy changes occurring during a chemical reaction

Endothermic Reactions

• a reaction that absorbs energy; ΔH is positive (+)

Exothermic Reactions

a reaction that releases energy; ΔH is negative (-)

Activated Complex

a short-lived, unstab;e arrangements of atoms that exists at the peak of the activation energy barrier during a chemical reaction; represents the highest energy point between reactants and products; TS = transition state

Activation Energy

the minimum amount of energy required for a chemical reaction to occur