What defines dynamic equilibrium in IB Chemistry?
The rate of the forward reaction equals the rate of the reverse reaction.
What principle predicts how equilibrium responds to stress?
Le Chatelier’s principle.
What is the IB definition of reaction rate?
Change in concentration per unit time.

At equilibrium, is the reaction product or reactant favored?
Product favored
Dynamic equilibrium must occur in a _________ system.
Closed
In a closed system at equilibrium, what happens to concentrations?
They remain constant.
What happens to equilibrium if you remove a product?
Equilibrium shifts toward products.
What theory explains reaction rate in IB Chemistry?
Collision Theory

Is this reaction exothermic or endothermic?
Exothermic.
What is the value of ΔH for an exothermic reaction?
Negative
What does the equilibrium constant (Kc) measure conceptually?
The position of equilibrium.
Increasing concentration of products causes equilibrium to…
shift toward the reactants.
What makes a collision successful?
Correct orientation and energy ≥ activation energy.

Which sample has a lower molecular mass?
Y. With a lower mass, more particles will have a higher velocity (more spread out Maxwell-Boltzmann distribution).
What is the only factor that changes K (equilibrium constant)?
Temperature
What happens to equilibrium when a catalyst is introduced?
Equilibrium is reached faster. The equilibrium itself does not shift or change.
In an exothermic reaction, increasing the temperature causes the equilibrium to...
shift towards the reactants.
What does increasing temperature do to rate?
Increases frequency of successful collisions.

What does "n" represent on the energy profile diagram?
Activation energy when a catalyst is introduced.
Explain equilibrium at a particle level for a reaction with a K value of 4.2 x 10^34.
At equilibrium, the reaction consists of majority products with a negligible amount of reactants.
How do you construct a Kc expression (IB wording)?
Concentration of products divided by concentration of reactants, each raised to stoichiometric coefficients.
Increasing pressure shifts equilibrium toward…
The side with fewer moles of gas.
How does a catalyst speed up a reaction?
Decreases activation energy so more particles have enough energy to college and form products.

At equilibrium, would you expect the equilibrium constant to be less than, equal to, or greater than 1?
Reactant favored. K is less than 1.
When using Hess's Law for equilibrium, if you have to flip an equation, what do you do with the K value?
Inverse of K.