-
Kinetics
kinetics is the study of the factors that affect the speed of a reaction and the mechanism by which a reaction proceeds
-
4 factors that influence the speed of a reaction:
- nature of the reactants (physical states (s,l,g) surface area)
- temperature,
- catalysts,
- concentration
-
what do catalysts do
speeds up the reaction by lowering the activation energy
-
There are three types of reaction rates
1) Average Rate: 2) Instantaneous Rate: 3) Initial Reaction Rate:
-
2) Instantaneous Rate:
Provides the rate of a reaction at a given moment.
-
3) Initial Reaction Rate: .
Is the instantaneous reaction rate at the moment the reaction starts
-
Instantaneous Rate -Determined from the
slope of a tangent to the concentration vs time curve at a specified time.
-
Rates of reactions depend on
concentration of reactants
-
The more starting material you have, the------------ a reaction will proceed.
faster
-
Second order – rate quadruples when ---------- concentration (exponential)
- doubling
- M/s = k (M)2 k = M-1s-1
-
Zero order = relationship to concentration?
- independent of concentration
- Rate = k[A] M/s = k (M) k = M/s units
-
Most reactions do not contain
only one reactant
-
Reaction (Rate) Constant -
A proportionality constant relating the concentrations to the reaction rate.
-
If x,y, and z are added together, what does that equal
the total
-
Half-Life, t1/2 -
time required for the concentration or amount of a sample to decrease by 50%.One-half of the sample reacts each half-life.
-
The minimum amount of energy required to reach the transition state is referred to as the
Energy of Activation.
-
Upon collision, a chemical reaction occurs as reactants pass through ------------in which bonds are being broken and new bonds are being formed.
a transition state
-
The rate of a chemical reaction is dependent upon ------------
its energy of activation.
-
Those reactions that have a high energy of activation tend to proceed -----------
slowly
-
Reactions that have a small energy of activation tend to proceed ------
rapidly
-
A catalyst is a substance that
speeds up a reaction but is not consumed in the process. (lowers activation energy required)
-
elementary steps, meaning that they cannot ------and that the molecules actually------------
- 1be broken down into simpler steps
- 2interact directly in this manner without any other steps
-
molecularity
the number of reactant particles in an elementary step
-
a unimolecular step involves -------------
a bimolecular step involves-------------
- 1 reactant particle
- 2 reactant particlesthough they may be the same kind of particle
-
rate determining step
- the slowest step has the largest activation energy
- product production cannot occur any faster than the slowest step – the step determines the rate of the overall reaction
-
|
|