chemical equilibria Flashcards
(44 cards)
how is it often denoted that a reaction is reversible
using a double headed arrow
where can an equilibrium only be established
in a closed system
where can equilibrium be set up from
either direction
what is reached at equilibrium
a natural balance between products and reactants
why are chemical equilibria dynamic
both the forward and reverse reactions continue to occur
rate of forward reaction equals…
rate of reverse reaction
the concentrations of reactants and products remain constant unless…
the conditions are changed
what can changes to the conditions of an equilibrium affect
the position of the equilibrium
le chateliers principle
if a system in equilibrium is subjected to change, the position of the equilibrium will move in the direction which opposes that change
when will the equilibrium shift to the right
if the conc of reactant is increased/conc of product decreased
when will the equilibrium shift to the left
if the conc of reactant in decreased/conc of product increased
which side does the equilibrium shift to if the total pressure is increased
to the side with fewer moles of gas because fewer moles of gas exert less pressure
which side does the equilibrium shift to if the total pressure is decreased
to the side with more moles of gas because more moles of gas exert more pressure
what effect does an increase in pressure have on the rate of reaction
increases rate of reaction
why does increased pressure increase rate of reaction
collisions between molecules are more frequent
which direction will the equilibrium move in if the temp is increased
the direction of the endothermic reaction (TAKES HEAT IN)
which direction will the equilibrium move in if the temperature is decreased
the direction of the exothermic reaction (GIVES OUT HEAT)
what does the way the equilibrium responds to change in temperature depend on
whether the forward reaction is exothermic or endothermic
what does an increase in temperature always increase
the rate of the forward and backward reactions but to different extents
what does a catalyst increase the rate of the forward and backward reactions by
the same amount
what effect does a catalyst have on the equilibrium position/yield
none
what does using a catalyst increase
the rate at which the equilibrium position is reached
the haber process
N2(g)+3H2(g)> 2NH3 (g)
what is dependent on the conditions used in the haber process
the equilibrium position, yield of ammonia and rate of reaction
