Equilibria Flashcards
What do reversible reactions give rise to?
A state of equilibrium (equal)
Why is the rate of the forward reaction high at the start of an experiment?
The concentration of the reactants is high
Why is the rate of the backwards rea tion initially 0?
There are no products yet
What happens as the reaction continues?
The concentration of the reactants decrease while the concentration of the products increases. This continues until the two reactions become equal.
When is equilibrium possible?
In a closed system, where no substances are added or removed.
What is le chateliers principle?
That an equilibrium will move in order to undo any change forced upon it
What happens to equilibrium due to an increase in concentration?
Equilibrium moves away from the increase to use up the extra substance (making more product)
What happens to equilibrium due to a decrease in concentration?
Equilibrium shifts towards the decrease to make more of the removed substance (making more reactant)
What happens to equilibrium due to an increase in temperature?
Equilibrium shifts to take in the extra heat (favours the endothermic reaction)
What happens to equilibrium due to a decrease in temperature?
Equilibrium shifts to release heat energy (favours the exothermic reaction)
What happens to equilibrium due to an increase in pressure? (Gases only)
Increase in pressure reduces the volume so equilibrium shifts in favour of the lower number of moles of gas
What happens to equilibrium due to a decrease in pressure? (Gases only)
Decrease in pressure increases the volume so equilibrium shifts in favour of the higher number of moles of gas
What happens to equilibrium due to the addition of catalyst?
The position of equilibrium isn’t affected, but the activation energy is reduced allowing the equilibrium to establish quicker
