Kinetics Lecture 1 Flashcards
What is the rate of reaction?
The rate at which a chemical reaction occurs
Is kinetics related to how far a chemical reaction goes, or how fast it goes?
How fast it goes
What can the rate of reaction be measured by?
Determining how the concentration of a reactant or product changes with time
What is the units for rate of reaction?
MolL -1 s-1
Where is the speed (velocity) found?
From the gradient of the graph
What is the gradient of the graph called?
A rate
How are all rate laws determined?
Experimentally
What factors affect reaction rate?
- Chemical nature of the reaction
- Physical States of the reactants and products
- Concentrations of the reactants
- Temperature
- Presence of catalyst or an inhibitor
In the rate law, what are x and y?
The ORDERS of the reaction
What is k in the rate law?
The rate constant
What order reaction is it if x+y= 0?
Zero order reaction
What order reaction is it if x+y=1?
A first order reaction
What order reaction is it if x+y= 2?
A second order reaction
What is the units of a zero order reaction?
MolL-1 s-1
What is the units of first order reactions?
s-1
What is the second order reaction unit?
Mol-1 Ls-1
What does the rate law involve? Reactants or products?
Reactants only
Why are some second order reactions appear as first order reactions?
Because one reactant (B) has a much larger concentration.
[B] will be approx constant as reaction occurs
What does the rate law become of reactions that are second order but appear first?
Rate = k'[A] K' = k[B] (constant)
What are the reactions called when they are second order but appear first?
Pseudo first order reactions
What is the affect as [A] doubles with zero order?
No change
What is the effect as [A] doubles with first order?
Rate doubles
What is the effect as [A] doubles with second order?
Rate increases x4
