All Flashcards
What are the differences between Thermodynamics and Kinetics?
Thermodynamics: Determines if a reaction can happen (spontaneous/non-spontaneous), considers Gibbs Free Energy (ΔG). | Kinetics: Determines how fast a reaction happens, considers reaction rates and activation energy.
Compare catalyzed vs. uncatalyzed reactions in terms of activation energy.
Catalyzed Reaction: Lower activation energy due to an alternative pathway. | Uncatalyzed Reaction: Higher activation energy, requiring more energy for the reaction to occur.
What are the differences between a spontaneous reaction and a fast reaction?
Spontaneous Reaction: A reaction that has a negative ΔG and is thermodynamically favorable. | Fast Reaction: A reaction that proceeds quickly due to a low activation energy or the presence of a catalyst.
Compare the effect of a catalyst on ΔG and activation energy (Ea).
ΔG: Catalyst has no effect on the Gibbs Free Energy change of the reaction. | Activation Energy (Ea): Catalyst lowers the activation energy, speeding up the reaction.
Define Thermodynamics.
The study of energy and its transformations; in chemistry, it determines if a reaction can occur (spontaneity).
Define Kinetics.
The study of reaction rates and mechanisms; it determines how fast a reaction occurs.
Define Activation Energy (Ea).
The minimum energy required for a reaction to occur.
Define Catalyst.
A substance that speeds up a reaction by providing an alternative reaction pathway with a lower activation energy; it doesn't change the thermodynamics (ΔG).
Define Reaction Rate.
How quickly reactants turn into products, measured as the change in concentration over time.
Define Kinetic Control.
A situation where the rate of a reaction is slow due to a high activation energy, even if the reaction is thermodynamically favorable (spontaneous).
What is the effect of a high activation energy on a reaction?
The reaction proceeds slowly, even if it is thermodynamically favorable.
What is the effect of a catalyst on a reaction?
The reaction rate increases because the catalyst provides an alternative pathway with a lower activation energy.
What is the effect of a negative ΔG on a reaction?
The reaction is spontaneous, meaning it is thermodynamically favorable, but it doesn't guarantee a fast reaction.
What happens when a catalyst is added to a reaction under kinetic control?
The reaction rate increases, as the catalyst lowers the activation energy, allowing the reaction to proceed faster.
What is the effect of increasing the concentration of a reactant on the reaction rate (assuming it's not zero order)?
The reaction rate generally increases, as described by the rate law (R = k[A]^n[B]^m).