Equilibrium Flashcards
What is homogenous equilibrium?
It all has the same state in the equation.
Kc expressions have the concentrations of all species.
What is heterogeneous equilibrium?
There are different states present in the equation.
The concentration of solids and liquids are constant, so are left out of Kc.
What does Kc include?
Only gas and aqueous species.
What is the Kp constant?
Equilibrium with gases use Kp - in terms of partial pressure as easier to measure concentration that pressure.
Kp has a direct relationship with Kc.
What is the mole fraction equation?
Moles of individual gas / total moles in system.
Must add to 1 as it is the fraction of the gas in the system.
What is p equal to?
p = equilibrium partial pressure.
How is partial pressure of individual gases calculated?
Partial pressure x total pressure (pressure certain gas adds to system).
What does Kp include?
Only includes gases, round brackets with p at the front.
How is Kp calculated?
- Write Kp expression
- Find partial pressures
- Substitute into equation
What are basic principles of le Chatelier?
If concentration increases, equilibrium shifts to decrease the concentration.
If pressure increases, equilibrium shifts to the side with the fewest gaseous moles.
If temperature increases, equilibrium shifts the endothermic way.
How do you know where the position of equilibrium is?
Kc =1, halfway
Kc > 1, products
Kc < 1, reactants.
How does Kc change in an exothermic reaction?
Kc decreases as temperature increases. Increasing temperature, decreases yield.
What affects Kc?
Temperature.
At a set temperature, Kc does not change even if other factors eg. concentration does.
How does Kc change in an endothermic reaction?
Kc increases as temperature increases. Increasing temperature, increases yield.
How can equilibrium shift?
As Kc does not change.
