chemical kinetics Flashcards
What is reaction order?
How much the concentration of a reactant affects the reaction rate
What does it mean when a reaction is zero order?
Concentration has no effect on rate
What does it mean when a reaction is first order?
When concentration increases by 1, rate increases by 1
What does it mean when a reaction is second order?
When concentration increases by 1, rate increases by 2
What is the rate law?
k([A]^order of A)([B]^order of B)
How do you find reaction order?
Reaction order must be determined experimentally
What is the integrated rate law for first order reactions?
ln[A]t = -kt + ln[A]0
What is the integrated rate law for second order reactions?
1/[A]t = kt + 1/[A]0
What is half-life?
Time for half of a reaction to be consumed
What is half life for zero order reactions?
[A]0/k
What is the half life for first order reactions?
0.693/k
What is half life for second order reactions?
1/k[A]0
How does concentration affect rate of reaction?
The rate of reaction increases with increasing concentration
How does activation energy affect rate of reaction?
The rate of reaction decreases when activation energy increases
What is activation energy (Ea)?
Minimum energy needed to break bonds (minimum energy to start reaction)
How does temperature affect rate of reaction?
Rate of reaction increases with temperature
What is the arrhenius equation used for?
Comparing reaction constant at 2 different temperatures
What is an elementary step?
One individual step in a reaction
What is an intermediate?
An element that appears on both sides of a reaction
What is the rate determining step?
The slowest step in a reaction
What is molecularity?
The amount of molecules involved in one step on the reactant side
What is an energy profile
A graph of energy vs progress of reaction
How do you determine the number of steps a reaction has from the energy profile?
Count the number of peaks
What is an elementary reaction?
A reaction with 1 elementary step
