Chemical Industry 2: Equilibria Flashcards
How does concentration of reactants effect equilibrium position
- increase conc of reactants = shift right
- decrease conc of reactants = shift left
How does concentration of products effect equilibrium position
- increase conc of products = shift left
- decrease conc of products = shift right
How does pressure effect equilibrium position
- increase pressure = shift to side with fewer gas molecules ( moles )
- decrease pressure = shift to side with more gas molecules ( moles )
What are the 2 rules for pressure effecting equilibrium position
- Only affects reactions involving gasses
2. Only has an effect if there are different numbers of gas molecules on each side
How does temperature effect equilibrium position
- Increase temp = moves to +ve ENDOthermic direction ( take heat in )
- decrease temp = moves to -ve EXOthermic direction ( let more heat out )
( both brackets ie. to compensate for lost or extra heat )
How does a catalyst effect equilibrium position
It doesn’t effect position but equilibrium attained faster
What does Kc stand for
equilibrium constant
What is the only condition that changes Kc
Temperature
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
What is the significance of Kc = 1
Equal concentration of products and reactants
What is the significance of Kc > 1
Equilibrium lies to the right ( more products than reactants )
What is the significance of Kc < 1
Equilibrium lies to the left ( more reactants than products )
How does temp affect Kc explain
If heat increase and forward reaction is EXOthermic ( I.e shifts left = less products ) Kc decreases
How to work out Kc given an equation part of an experience
ICE diagrams ( look at notes on how to do them )
