chemmmm eq

• a system that may exchange energy but not matter with its surroundings 
• when chemical changes are studied it is easier when the system is seperated from its surroundings (definate physical boundry)

a balance between forward and reverse process occuring at the same time (opposing changes must be occuring at equal rates)

in an equilibrium equation the left to right reaction

in an equilibrium equation the right to left reaction

a dynamic equilibrium between a solute and a solvent in a satruated solution in a closed system

A saturated solution is a solution in which the maximum amount of solute has been dissolved.

a dynamic equilibrium between different physical states of a pure substance in a closed system

a dynamic equilibruim between reactants and products of a chemical reaction in a closed system 

if solution is in a closed system then the observable properties of the solution become constant 

process of dissolving 

particles are always moving and collisions are occuring even if no changes are observed 

when solute is first added many more ions dissociate from the crystal than crystalize into it 

as more ions come into the solution more ions also crystalize 

at solubility eq solute ions dissolve and crystalize at the same rate (no observable changes occur in concentration ions. quantity of solid present)

• in a closed system evaporation occurs when molecules collide and gain energy to start a second phase (gas state)
• condensation occurs when number of gas molecules increase and collde with the surface of liquid and lose energy become liquid 
• as time pases the rate of evaporation and condensation become equal (phases occur but no change is observed)
• pressure in gas phase remains the same

higher temperature therefore concentration and pressure of gas increases if eq is reached at a higher temp

open systems

• reached at melting and boiling point
• if ice was placecd in warm water (ice melts fasternthatn water freezing therefore melgint =net change
• as the temp of water decreases the rate of melting dec and the rate of freeing inc until temp is 0 deg then rates become equal )

• a reactio in which virtually all of the limiting reagent is consumeed (in open system no eq)
• only occur in closed systems

a competition bw collisons of reactants to form products or products to form reactants 

a reaction that can achieve eq in the forward or reverse direction

whether eq is approached in the forward or reverse 

• the tield of product measured at eq compared with the maximum possible tield of product 
•  

percent reation =actual product yield / theoretical produt yield x100%

reactions that favor reactants very strongly (mixing reactants have no obervable result)

reactions that favor products very strongly (observed as complete or quantatative written with single arrow)

reactants are fav with noticeable eq conditions

products are fav with noticeable eq conditions

the value obtained by the mathematical combination of eq oncentrations using the eq law expression

chemical entities in gas or aq phase 

coefficients from balanced eqation

• products are written in the numerator
• reactants are written in the denominator
• coefficients of balanced eqation=exponents
• concentrations in eq law expression =molar concentrations of entities at eq

forward reaction

reverse reaction

• rate constant for Vf 
• Vf=Kf [A][B]

• rate constant for Vr
• Vr=Kr[C][D]

• equal 
• Vf=Vr

temperature

the position of eq is a measure of the extent to which reactants become products in a closed system 

temp and concentrations

eq in which reactants and products are in more than one phase

ew in which all entities are in the same phase

provides a measure of the extent to which the raction has gone to completion when eq is reached

the reaction proceeds to completion the concentrations of products are much greater tht the concentrations of reactants at eq

the concentration of reactants and products are approximately equal to eq

• very small amounts of products formed
• the concentrations of reactants are much greater that the concentrations of products at eq

• when a chemical system at eq is disturbed by a change in a property the systed adjusts in a way that opposes the change
• includes : 
• initail eq state
• shifting non eq state
• new eq state

• that system will undergo a eq shift
• reactant concentration decreases
• some of added reactant changes to products
• new eq state is formed 
• shift fwd (right)

• concentration of products increase
• the reactants decrease untill a new eq is stablished
• eq shift forward 

the initail k value and final k value remain the same

with more reactant particles present per volume collisions are suddenly much more requent for the forwards reaction 

increase in reactant = forward reacton increse in products

• as concentration of product increases so does the recerse reaction rate
• as reactant is consumed forward reaction rate decreases 
• continue until the 2 rates become equal to eachother

facster thatn the origninal because the system containses a larger number of particles (more collisions) in dynamic eq

• less particles pre volume ollisions are less frequent causing dwd reverse reaction
• decrease reactant =reverse reaction 

energy in chem eq can be treated as reactant / product

reactants+energy <> products

reactants<> products + energy

eq shifts in the direction that produces heat

eq shifts in the direction that absorbs heat

• the system will react in a wat that resists the change
• liquids or solids not affected
• equal # of gas molecules oneach sde are not affected

shifts towards the side with the larger total amount of gaseous entities

shifts towards the side with thte smalller total amount of gaseous entities

catalyst

inert gases

noble gas or non reactive gas 

a test calculation using measured concentration values of a system in the equilibrium expression

system at eq

system shifts left (product reactant ratio too high)

system shifts right (product reactant ratio is low)

excess solute is in eq with its aq solution

with excess salt and issolvint it until solution is aturated and excess solute remains

mimxing solutions of two sals

the concentration of a saturated solution of a solute in a particular solvent at a partifuclar tempertaure (specific maximum concentration)

ksp is the value obtained from the eq law applied to saturated solution

the reaction quotent applied to the ion concentrations of a slightly soluble salt

ksp and q values are compared 

ion product of a saturated solution in which dissolved and undissolved solutes are in dynamic eq

• solution is unsatruated
• not capable of dissolving more ions 
• will not form a precipitate

more ions in solution than necessary for solution = super saturated solution (solute concentration exceeds the eq concentration)

super saturated precipitate will form

saturated precipitate will not form

unsaturated precipitate will not form

when eq exists in a solution involving ions it can be shifted by dissolving into the solution that adds a common ion 

a reduction in the solubility of a salt caused by the presence of another salt having a common ion