equilibria Flashcards
5 features of a chemical equilibrium
- closed system
- both reactants and products are present at all times
- equilibrium can be approached from either side
- reaction is dynamic (moving backwards & forwards at the same rate)
- conc remains constant
le chatelier’s principle
when a change is applied to a system in a dynamic equilibrium, the system reacts in such a way as to oppose the effect of the change
if exo, where does it shift when increasing temp
left
if exo, where does it shift when decreasing temp
right
if endo, where does it shift when increasing temp
right
if endo, where does it shift when decreasing temp
left
what does adding a catalyst do to an equilibrium
increases rate of attainment
what happens to the eq when you add more conc
it will shift to oppose the change
what is Kc affected by
change in temp
what happens to kc if increased in temp in an exo reaction
decrease
what happens to kc if temp is decreased in an exo reaction
increase
what happens to kc if temp is increased in an endo reaction
increase
what happens to kc if temp is decreased in an endo reaction
decreased
meaning of equilibrium constant (Kc)
a value that expresses the relationship between the conc of products and reactants present at the eq in a reversible reaction
heterogeneous system
a system where not all chemicals are in the same phase
homogenous system
a system where all the chemicals are in the same phase
reversible reaction
reactions in which the products from the reaction can react together to form the original reactants.
direction of reversible reaction can be changed by changing the conditions
2 features of a reaction at equilibrium
forward rate = backward rate
the concentration remains constant
why the industry uses a temperature higher than 600k
higher rate of reaction
state why the industry uses a pressure lower than 35MPa
less electrical pumping cost
meaning of the term catalyst
a substance that speeds up a reaction without being chemically used up
how does a catalyst work
it provides an alternative route without being used up and lowers the activation energy
