equilibrium Flashcards
rate
measure of the speed of any change that occurs within an interval of time
how are rates of chemical reactions measured
change in the number of moles during an interval of time
collision theory
atoms, ions, and
molecules can react to form products when they
collide with one another, provided that the
colliding particles have enough kinetic energy.
activation energy.
The minimum energy that colliding particles
must have in order to react
activated complex
an unstable
arrangement of atoms that forms momentarily at
the peak of the activation-energy barrier.
transition state.
another name for activated complex
The rate of a chemical reaction depends
upon
temperature, concentration,
particle size, and the use of a catalyst.
inhibitor
a substance that interferes
with the action of a catalyst.
reversible reaction
one in which the
conversion of reactants to products and
the conversion of products to reactants occur
simultaneously.
At chemical equilibrium,
no net change occurs in
the actual amounts of the
components of the system.
chemical equilibrium.
When the rates of the forward and
reverse reactions are equal,
the reaction has reached a state
of balance called
equilibrium position
The relative concentrations of the reactants and
products at equilibrium
equilibrium constant (Keq)
the ratio of product
concentrations to reactant
concentrations at equilibrium,
For all Keq,
·Units are omitted
·Regardless of initial [ ] the reaction
will establish equilibrium.
·Equilibrium can be obtained from either direction
of the reversible reaction
·Each set, or trial of equilibrium [ ] is called an
equilibrium position.
Homogeneous equilibria
all reactants and
products are in the same state
Heterogeneous equilibria
substances
are in more than one state
what forms can be used?
Only use those in gaseous
(g) and aqueous (aq) forms;
ignore those in solid (s) or
liquid (l) forms
·At equilibrium, the
forward and reverse
reactions are
proceeding at the same
rate.
Once
equilibrium is
achieved,
the amount of each reactant and product remains constant.
·If K»1,
the reaction
is product-favored;
product
predominates
·If K
the
reaction is
reactant-favored; reactant
predominates
a Reaction Quotient
If the system is not at
equilibrium the ratio is known
as
If Q > Keq
the product side
is too high and the equilibrium
will shift to the left to restore
equilibrium
If Q
the product side
is too low and the equilibrium
will shift to the right to
restore equilibrium
Le Châtelier’s principle:
If a stress is applied to a system
in dynamic equilibrium, the system
changes in a way that relieves the stress.
when you decrease pressure, the system shifts to the
direction the
produces more moles of gas.
solubility product constant (ksp)
the product of the concentrations of the ions, each raised o a power equal to the coefficient of the ion in the dissociation equation
common ion
ion found in both salts in a solution
common ion effect
if the product of the concentrations of two ions in the moixture is greater than the ksp of the compound formed from the ions, a precipitate will form
