Detailed Breakdown: Kinetics
The Collision Model of Kinetics: Reactions only occur when particles collide with sufficient energy (Activation Energy, $E_a$) and correct orientation. Temperature increases are far more effective than concentration increases because they exponentially increase the fraction of particles with $E \geq E_a$.
Reaction Rate and Order: The rate of reaction represents the change in concentration over time. The 'order' of a reaction describes exactly how sensitive the rate is to a specific reactant's concentration; this can only be determined by experiment, not by looking at the balanced equation.
Reaction Mechanisms and the Rate Determining Step (RDS): Most reactions aren't one-step events. They occur as a series of elementary steps. The slowest step (RDS) dictates the overall speed and determines the rate law. Catalysts provide an alternative path with a lower RDS energy barrier.