Study sets, textbooks, questions
Upgrade to remove ads
Chemical Kinetics and the Nucleus, a Chemist's View
Terms in this set (30)
The study of the changes in concentrations of reactants or products as a function of time
-*study of reaction rates*
Each reaction has its own characteristic rate.
The reactions may be slow, fast, or reversible.
What affects reaction rates
Concentration, physical state, temperature, use of a catalyst/inhibitor
Molecules must collide in order to react.
Physical state's effect
Molecules must mix in order to collide
Molecules must collide with enough energy to react
[A] means concentration of A in mol/L; A is the reactant or product being considered.
Change in concentration of a reactant or product per unit time
The change in concentration of reactants (or products) over a finite time period
The reaction rate at a particular time, given by the slope of a tangent to a plot of reactant concentration vs. time
The instantaneous rate at the point at which the reactants are mixed (t = 0)
An expression showing how the rate depends on the concentrations of reactants
Rate Law Equation
Rate = k[A]ⁿ
The concentrations of the products do not appear in the rate law because
This particular rate is being studied under conditions where the reverse reaction does not contribute to the overall rate.
n in rate law equation
Must be determined by experiment; it cannot be written from the balanced equation
rate = k [A]
M/s = ? M
*k is s⁻¹ or 1/s *
rate = k [A]²
M/s = ? M²
*k is M⁻¹s⁻¹ or 1/(Ms)*
rate = k
M/s = ?
*k is M/s*
A positive or negative exponent, for a reactant, for which the concentration is raised to in a rate law
2 types of rate laws
Differential rate law and integrated rate law
Differential Rate Law
Shows how the rate of reaction depends on concentration
(often called simply the rate law)
Integrated Rate Law
Shows how the concentrations of species in the reaction depend on time
Because the differential and integrated rate laws for a given reaction are related in a well-defined way
The experimental determination of either of the rate laws is sufficient
Experimental convenience usually dictates
Which type of rate law is determined experimentally
Knowing the rate law for a reaction is important mainly because
We can usually infer the individual steps involved in the reaction from the specific form of the rate law
Determining the form of the rate law
-The first step in understanding how a given chemical reaction occurs is to determine the form of the rate law.
-We must determine experimentally the power to which each reactant concentration must be raised in the rate law.
An exponent of "1" is referred to as
An exponent of "2" is referred to as
Overall reaction order
The sum of the orders for the various reactants
Overall Reaction Order equation
The sum of the exponents in the reaction rate equation.
Rate = k[A]^n[B]^m
*Overall reaction order = n + m*
k = rate constant
[A] = concentration of reactant A
[B] = concentration of reactant B
Sets found in the same folder
Chem 4 - Rate and Order - To Memorize
Integrated Rate Law
Other sets by this creator
"Their Eyes Were Watching God" - Literary Terms Ex…
"Their Eyes Were Watching God" - Literary Terms
Zora Neale Hurston (1891 - 1960)
"Their Eyes Were Watching God" - Important Details