Physical - Chemical Equilibria etc. Flashcards
how is a reversible reaction represented?
⇌
in each reversible reaction, one reaction will be _____ and the opposite will be _____?
endothermic
exothermic
(either order)
dynamic equilibrium can only occur in what kind of systems?
closed
why can dynamic equilibrium only occur in closed systems?
because no substances can enter of exit in order to influence the reactions
what is le chatelier’s principle used to predict?
how an equilibrium mixture will change if the reaction conditions are altered
state the le chatelier’s principle
when a system is subject to change, the system will alter to lessen the effect of that change
why is le chatelier’s principle useful in industry?
so reaction conditions can be altered to maximise yield of desired product
what are homogeneous equilibria?
reactions where every species is in the same physical state
when does a reaction reach dynamic equilibrium?
- the reactions are proceeding at the same time
- rate of the forwards reaction is equal to the rate of the backwards reaction
- concentrations of reactants and products become constant
what is the effect of increasing concentration of reactants?
- equilibrium shifts right
- favours the products
what is the effect of decreasing concentration of products?
- equilibrium shifts right
- favours the products
what is the effect on equilibrium of increasing concentration of products?
- equilibrium shifts left
- favours the reactants
what is the effect on equilibrium of decreasing concentration of reactants?
- equilibrium shifts left
- favours the reactants
what is the effect on equilibrium of increasing pressure?
equilibrium shifts in the direction of fewer molecules
what is the effect on equilibrium of decreasing pressure?
equilibrium shifts in the direction of more molecules
