Test 3 Flashcards
collision theory
A model that explains reaction rate as based on the number, every, and orientation of colliding particles.
Arrhenius equation
An equation that expresses the exponential relationship between temperature and the rate constant.
activation energy
The minimum energy with which molecules must collide to react.
effective collision
A collision in which the particles meet with sufficient energy and orientation that allows them to react.
frequency factor
The product of the collision frequency Z and an orientation probability factor p that is specific for a reaction.
transition state theory
A model that explains how the energy of reactant collisions is used to form a high-energy transitional species that can change to reactant or product
transition state
An unstable species formed in an effective collision of reactants that exists momentarily when the system is highest in energy and that can either form products or re-form reactants
reaction energy diagram
A graph that shows the potential energy of a reacting system as it progresses from reactants to products
reaction mechanism
A series of elementary tips that sum to the overall reaction and is consistent with the rate law
elementary reaction
A simple reaction that describes a single molecular event in proposed reaction mechanism
molecularity
The number of reactant particles involved in a elementary step
unimolecular reaction
An elementary reaction that involves the decomposition or rearrangement of a single particle.
bimolecular reaction
An elementary reaction involving the collision of two reactant species
rate-determining step
The slowest step in a reaction mechanism and therefore the step that limits the overall rate.
reaction intermediate
A substance that is formed and used up during the overall reaction and therefore does not appears int he overall equation
catalyst
A substance or mixture that increases the rate of a reaction without being used up in the process.