Chapter 15 Flashcards
what is reaction rate?
how fast the reaction occurs
how are rates expressed?
as a change in quantity (either pressure or concentration) over time
what happens to the reaction concentration with respect to time and why?
it decreases because reactants are consumed
what happens to the product concentration with respect to time and why?
in increases because products are made
give 3 units of rate
change in concentration over change in time, molarity per second, atmospheres per second
what do you look at for average rates?
concentration or pressure change over given time interval
what do you look at for instantaneous rates?
slope of tangent line at given time
what is a rate law?
the relationship between the rate of the reaction and the concentration of the reactant(s)
what are reaction mechanisms?
series of individual chemical steps by which an overall chemical reaction occurs; detailed description of reaction at a molecular level
what is an elementary step?
can not be broken down into simpler steps, found in reaction mechanisms
define molecularity
how many molecules are interacting in a given step
what are reaction intermediates?
formed in one step and consumed in the next step, not presentin overall reaction, cancel out intermediates from individual steps to form overall reaction
what is a catalyst?
consumed in one step and formed in a later step, not present in overall reaction
what is the molecularity of
A –> products
unimolecular
what is the molecularity of A + A –> products
bimolecular
