Dynamic Equilibrium Flashcards
What is a dynamic equilibrium?
A forward reaction will be going at exactly the same rate as the backward reaction.
The amounts of reactants and products won’t be changing anymore, so it’ll seem like nothing’s happening.
It can only happen in a closed system (nothing can get in or out).
What is Le Chatelier’s Principle?
If there’s a change in concentration, pressure or temperature, the equilibrium will move to counteract the change.
What happens if you increase the concentration of the reactant in a dynamic equilibrium?
The equilibrium tries to get rid of the extra reactant. It does this by making more product so the equilibrium is shifted to the right.
What happens if you increase the concentration of the product in a dynamic equilibrium?
The equilibrium tries to remove the extra product. This makes the reverse reaction faster go faster so the equilibrium shifts to the left.
What does increasing the pressure do?
It shifts the equilibrium to the side with fewer gas molecules- reducing the pressure.
What does decreasing the pressure do?
It shifts the equilibrium to the side with more gas molecules- raising the pressure again.
How does the equilibrium shift if you increase temperature?
It shifts in the endothermic (delta H positive) direction to absorb this heat.
How does the equilibrium shift if you decrease temperature?
It shifts in the exothermic (delta H negative) direction to replace the heat.
What effect do catalysts have on the position of the equilibrium?
Catalysts have no effect on the position of the equilibrium.
They can’t increase yield- but they do mean equilibrium is reached faster.
Choosing a reaction you have studied that is catalysed by chlorine radicals, write down an equation for the overall reaction and show how chlorine radicals are not consumed by the overall reaction.
Cl + O3 -> ClO + O2
ClO + O -> Cl + O2
overall: O3 + O -> 2O2
Suggest ways in which the use of catalysts help chemical companies to make their processes more sustainable.
catalyst not used up in reaction
reactions take place at lower temperatures with lower energy demand so less carbon dioxide emitted into atmosphere
different reactions can be used with better atom economy
