Kinetics
Factors AffectingRalesi
rate 2 collision frequency 8 energy
1 Concentrations of reactants
2 Physical state of reactants
3 Temperature
4 Addition of catalyst
collisionTheory Basis of the RateLaw
Particlesmust collide in order toreact
P in concentration of a reactant leads to 9 collisions E Preaction rate
of collisionsdepend on the product of the ofreactant particles nottheirsum
KMT can beused to calculate collision density
Ex gasesundergo ILS
1030 collisions hear STP if every collision yieldedproduct then theoreticalrate 106Mt
actualrates are severalorders of magnitudeless typical actualrate to 3Mls Soonly a fraction of
collisions yield a run
Collision Theory
Reactions require
1 activationenergy
2 correct geometry
Reactionprofilesi
Theactivatedcomplex is a hypothetical specieslying betweenreactants r products at a
, point on the run profilecalled the transitionstate
Reactionprofile diagram of energyvs reactionprogress
Effect of temperature on Rate constants
P temperature 9 reactionrates 2 rateconstants
very fewexceptions to thisrole
an enzyme catalystreaction can begin to slowdown as the temperature is increased since the
enzyme can become denatured at high temperature
Effect of T on collision frequency
If activation barrier is high only a fewmolecules have sufficient kineticenergyor the reaction
is slower
As temperature P reaction rate P
Effect of temperature on Reaction Ratesi
Arrhenius demonstrated that
many rateconstants vary with temperature according to
the equation i k Ae EaIRT A pre exponential factor
In K LEf Ly In A
Temperature dependence of Ki
For graphs of Ink YT y mxtb Ink LEf Ly In A
vs t
slope inclercept _In A
EPI k InA
Slope
thk
HT
Factors AffectingRalesi
rate 2 collision frequency 8 energy
1 Concentrations of reactants
2 Physical state of reactants
3 Temperature
4 Addition of catalyst
collisionTheory Basis of the RateLaw
Particlesmust collide in order toreact
P in concentration of a reactant leads to 9 collisions E Preaction rate
of collisionsdepend on the product of the ofreactant particles nottheirsum
KMT can beused to calculate collision density
Ex gasesundergo ILS
1030 collisions hear STP if every collision yieldedproduct then theoreticalrate 106Mt
actualrates are severalorders of magnitudeless typical actualrate to 3Mls Soonly a fraction of
collisions yield a run
Collision Theory
Reactions require
1 activationenergy
2 correct geometry
Reactionprofilesi
Theactivatedcomplex is a hypothetical specieslying betweenreactants r products at a
, point on the run profilecalled the transitionstate
Reactionprofile diagram of energyvs reactionprogress
Effect of temperature on Rate constants
P temperature 9 reactionrates 2 rateconstants
very fewexceptions to thisrole
an enzyme catalystreaction can begin to slowdown as the temperature is increased since the
enzyme can become denatured at high temperature
Effect of T on collision frequency
If activation barrier is high only a fewmolecules have sufficient kineticenergyor the reaction
is slower
As temperature P reaction rate P
Effect of temperature on Reaction Ratesi
Arrhenius demonstrated that
many rateconstants vary with temperature according to
the equation i k Ae EaIRT A pre exponential factor
In K LEf Ly In A
Temperature dependence of Ki
For graphs of Ink YT y mxtb Ink LEf Ly In A
vs t
slope inclercept _In A
EPI k InA
Slope
thk
HT
