Paper 1&2- Equilibrium Flashcards
(18 cards)
Define dynamic equilibrium
Both the forward and reverse reaction are occurring at an equal rate so there is no net change in the concentration of products and reactants
What are the conditions for equilibrium?
Reaction must be taking place in a closed system
Can be approached from either direction
Is a dynamic process
No changes to macroscopic properties such as colour
Define Le Chatelier’s principle
If a constraint is placed on a reaction at equilibrium, the equilibrium will move to oppose that constraint
How does equilibrium change when pressure is increased?
Shifts to side with fewer moles
How does equilibrium change when concentration of products is increased?
Shifts to left
How does equilibrium change when temperature is increased?
Shifts in endothermic direction
How does a catalyst affect equilibrium?
No change
What conditions are used in the Haber process?
450 celcius/ 725K
200 atm
Iron catalyst
What is the equation for the Haber process?
N2 + 3H2 (reversible) 2NH3
What 3 strategies are used in industry to maximise profit and yield in the production of ammonia?
Recycle unused reactants
Pass reactants over a catalyst
NH3 is cooled and tapped off
Give 5 uses of ammonia
Fertiliser
Nylon
Explosives
Drugs
Dyes
How to write expression for Kc
Product/ reactants
What is the only condition that causes Kc to change?
Temperature
Why does changing concentration have no effect on Kc?
Initially eqm will shift but will eventually return to original position
What does a low Kc value suggest about the position of equilibrium?
Equilibrium lies to left
What does a high Kc suggest about the position of equilibrium?
Equilibrium lies to right
What does a Kc less than 10^-10 suggest?
Reaction does not take place at all
What does a Kc greater than 10^10 suggest?
Reaction goes to completion
