Chapter 13: Kinetics: Mechanisms and Rates of Chemical Reactions
Way to determine rate of overall chemical reaction
Determined by rates of elementary reactions
Rate determining step
Elementary rxn that proceeds slower than any of other steps in mechanism. Governs rate of overall chem rxn.
study of rates of chem rxns
The reason stoichiometry isn't used for rate law for a reaction.
because orders must be determined experimentally
Cases where stoichiometry is acceptable to determine rate law.
Single elementary steps and rate limiting steps.
Three concepts of reaction mechanisms and rate laws.
. Mechanism is one or more elementary reaction that describes how chem reaction occurs sum of individual steps of mechanism gives balanced stoichiometric chem equation rate law predicted by mechanism is same as experimental rate law.
Units for zero order
units for first order
units for second order
specific heat of water?
F to C
concentration reactant at the beginning, concentration remaining at time t, and rate constant.
In the Order reaction equations what does [A]o, [A], and kt stand for?
the linear order
first order reactant eqn
amount of time required for half the amount of reactant to be consumed
the original concentration, [A]o
In first order reactions, what is half life independent of?
WHAT'S HALF LIFE FORMULA?
reciprocal of concentration varies linearly with time
second order reaction graph
concentration varies linearly with time
By examining how concentration changes
how can rate laws be determined?
energy of products is always higher than that of reactants
the energy always rises initially, but as bond forms, energy decreases.
the two "R" constants
Sequence of molecular events
molecular event during chem rxn with 1-3 reactants
Most common elementary reaction. Collision of two reactants
Elementary reaction where a single molecule breaks into two pieces and rearranges into a new isomer
Elementary reaction where three chem species collide simultaneously. Very rare.
Chemical species produced in early step of a mechanism and consumed in a later step. Never appears in overall reaction.
Define rate of reactions
Rate determining step
elementary rxn that procedes more slowly than any other step in mechanism. Governs overall chem rxn.