Exam 3 Flashcards
equilibrium constant
K
what does the equilibrium constant change with?
temp
what does a large K value mean?
reaction is product-favored
what does a small K value mean?
reaction is reactant-favored
what does chemical equilibrium mean?
forward rate=reverse rate
reaction quotient
Q
what causes system stress?
- addition/subtraction of a reactant/product
- altering partial pressures
- change in the volume while keeping a constant temp
what does an increase in temp in exothermic reactions mean?
a lower K value (they produce less)
what happens when Q>K?
the reaction occurs in the reverse direction
what affects equilibrium?
- change in the amount of product/reactant
- change in temp
- change in the volume of gas
which way does the reaction move when you add more reactant?
towards the products
what happens to a reaction when you change the volume of a gas?
change to the partial pressure
how does a decrease of 2 of the volume affect the partial pressure?
increases the partial pressure by 2
what does a decrease in the volume/increase in pressure move the reaction towards?
side with the lower number of moles
what does an increase in the volume/decrease in pressure move the reaction towards?
side with more moles
what does an exothermic reaction move the reaction direction towards?
reactants
what does an endothermic reaction move the reaction towards?
products
what does an increase in temperature do to the direction of a reaction?
forwards
what does a decrease in temperature do to the direction of a reaction?
reverse
RICE
reaction, initial concentration, changes, equilibrium concentration
if a reaction quotient has a smaller value than the equilibrium constant
the reaction will continue to make more products
increasing the temp in an exothermic reaction results in
more reactants and fewer products
Bronsted-Lowery acid definition
H ion donor
Bronsted-Lowery base definition
H ion acceptor
strong acid
- completely ionized
- K value is to large to calculate
- goes only in forward direction
weak acid
- partially ionized
- K is small enough to be calculated and used
- can go in reverse direction
conjugate base-acid pairs
differ by only a proton
the stronger the acid
the higher the K value
what does charge delocalization do?
stabilizes
autoionization
produces small equal concentrations of H30 and OH ions in pure water
what does a small K value mean
reaction doesn’t happen in the forward direction
strongest acid that can exist in water?
H3O
are strong acids all the same in water?
yea
what are strong acids converted into in water?
H3O
why are stable things weak?
not reactive
oxidation number
the greater the number of oxygen atoms the stronger the acid
the lower the pH…
the more acidic
pH neutral
7
pH>7
basic
pH<7
acidic
how does the oxidation number affect the K value?
makes it rise
pH+pOH=?
14
what does water auto ionize into?
OH and H3O
if [H3O] > [OH] is it acidic or basic?
acidic
if [H30] < [OH] is it acidic or basic?
basic
the weaker the acid…
the stronger the conjugate base
