Chapter 13 Key Terms Flashcards
Rate Constant (k)
A constant of proportionality
Rate Law
k[A]^n
Reaction Order (n)
The relationship between rate and concentration. n=0: rate is independent, n=1: rate is proportional to [A], n=2: rate is proportional to [A]^2
Overall Order
The sum of the exponents of multiple reactants
Integrated Rate Law
The relationship between [A] and time
Half Life (t 1/2)
The time it takes for [A] to decrease 50%
Arrhenius Equation
Relationship between k and temperature
k=Ae^(-Ea/(RT))
Activation Energy (Ea)
Energy barrier that must be overcome for a reaction to occur
Frequency Factor (A)
The frequency with which reactants approach Ea
Activated Complex
The transition state of a reaction
Exponential Factor
A number representing the fraction of molecules which have the energy to overcome Ea
Arrhenius Plot
A plot of ln[A] against T
Collision Model
A model where a reaction occurs due to an energetic collision between molecules. Replaces A with p*z
Orientation Factor
P, the factor in the collision model that is the fraction of molecules with correct orientation
Collision Frequency
z, the factor in the collision model that is the rate with which molecules collide
Reaction Mechanism
Series of individual steps which explain an overall chemical reaction
Elementary Step
One step in a reaction mechanism
Reaction Intermediates
Species which are used to explain elementary steps, but not present in the overall reaction
Molecularity
Number of reactant particles in a step
Unimolecular
One reactant in an elementary step
Bimolecular
Two reactants in an elementary step
Termolecular
Three reactants in an elementary step (very rare)
Rate Determining Step
The step with the slowest rate
Catalyst
Substance that increases rte of a chemical reaction but is not comsumed
