le chatelier's principle

adding OH^- to solution

reduces amount of H+, which will cause a shift on the side with H+

adding more solids don’t change the equilibrium

GAS or AQUEOUS moles

*may speed up the reaction?? double check??

when adding something to a reversible reaction at equilibrium,

it will not be completely “used up”

the amount goes up, decreases a little as it is used up, but more remains than originally at equilibrium

when removing something from a reversible reaction at equilibrium,

it won’t be completely replenished by shift

there will be less than the amount at the original equilibrium

cooling a reversible reaction shifts

toward the exothermic direction

heating a reversible reaction shifts

towards the endothermic reaction

if ΔH is on the product side

endothermic reaction is reverse, exothermic reaction is forward

if ΔH is on the reactant side

exothermic reaction is reverse, endothermic reaction is forward

K changes IF

TEMPERATURE changes

shift right w/ temp change

K increases

shift left w/ temp change,

K decreases

adding water to an aqueous system at equilibrium will

increase volume, shift to make more moles of solution

endothermic

product energy >> reactant energy

exothermic

reactant energy >> product energy

catalysts

do NOT affect equilibrium position, only speeds up the process of getting to the equilibrium

“flattens” the hill on curve, less energy needed

circle states of matter before you start!!!!

!!!!!

law of mass action

reaction rate is proportional to the product of the molar concentrations of the reactants, each raised to its coefficient

K_c

only gases and aqueous systems can have molarity

K_p

MUST be in atm

particle equilibrium

replace M with number of particles of each reactant/product

SOLIDS

may participate in ice charts, but NO molarities or atm

catalyst justification

catalysts don’t change equilibrium, they just speed up the process of getting to it

• equally speed up both forward and reverse rates

• lowers activation energy for both sides by the same amount

NO LIQUIDS!!! NO GASES!!!

while adding an inert gas will increase total pressure

no impact on partial pressures

equilibrium constant

NO correlation with speed of a reversible reaction, only forward/reverse rates

particle equilibrium

visually at equilibrium when respective numbers of particles stay the same

changes in pressure because of changes of volume & partial pressures

if pressure increases by decreasing volume of container, system responds by shifting to the side with fewer moles of gas, reducing the number of gas particles

• K_p remains constant

adding inert gas at constant volume

no changes to partial pressures

*IF K DOESNT CHANGE, PARTIAL PRESSURES REMAIN THE SAME bc no change in temp

*if pressure remains constant, adding inert gas will decrease partial pressures

aqueous systems & pressure changes

NOTHING!! BC ITS AQUEOUS AND DISSOLVED IN WATER

• increasing the pressure of a liquid does not change its volume!!!

be wary of states of matter!! always!!!!

!!!!

adding water to an aqueous system without water as a reactant or product

water dilutes all species equally, decreasing all concentrations

in order to maintain K value, equilibrium must shift towards the side with more moles of solute