Elements of the Sea: Equilibrium Flashcards
Definition of dynamic equilibrium (3)
- concentration of reactants and products stay constant
- forward and reverse reaction are both happening ( so dynamic )
- rate of forward reaction = rate of reverse reaction
How does concentration effect the position of equilibrium
If concentration is increased on one side of the equation equilibrium positions shifts to the opposite side to reduce concentration ( minimise change )
How does change in pressure effect equilibrium position
- Increase pressure = shift to side with fewer molecules ( smaller no. of moles ) = decrease pressure
- Decrease pressure = shift to side with more molecules ( larger no. of moles ) = increase pressure
How does change in temperature affects equilibrium position
- Increase heat = shifts in direction of ENDOthermic ( to take in extra heat )
- Decrease heat = shift in direction of EXOthermic ( gives out heat in order to compensate for heat lost )
How does a catalyst effects equilibrium position
- No effect
- only effect the rate
What does Kc stand for
Equilibrium constant
What is the equation for equilibrium constant( Kc)
What is the equation for equilibrium constant( Kc)
Kc = products / reactants
Write and expression for the equilibrium constant of
aA + bB <=> cC +dD
( where smell letter = mol ration of compound )
Kc = [C]^c [D]^d / [A]^a [B]^b
Write and expression for the equilibrium constant of
aA + bB <=> cC +dD
( where smell letter = mol ration of compound )
Kc = [C]^c [D]^d / [A]^a [B]^b
What is the rule for the units of equilibrium constant (Kc)
Each equilibrium constant has its own units
How do you work out the units of equilibrium constant
Look at sheet
When Kc > 1 what does it mean
More products then reactants at equilibrium
When Kc»_space; 1 ( greater than 10^10) what does it mean
Reaction appears to have gone to completion
When Kc < 1 what does it mean
More reactants than products
When Kc «_space;1 (less than 10^-10) what does it mean
Reaction appears not to have happened
