Tonstantchangeocuring
reactionisreversible
Ticalhanger Fance eathhmical
reactionhas anatural
equilibrium point
I
Forwardreaction y AB whenfudreactionisfavoured
equilibriumshiftsright
Reversereaction ATB Y whenns reactionisfavoured
equilibriumshiftsleft
CHEMICAL EQUILIBRIUM RATESOFREACTION
ensuresthattheamountofproduct reactant
Theratesofthe forward reversereactionsareequalatequilibrium sidewillremainthesame
oneither
scientistscanmanipulatetherateofreactiontoreachequilibriumfaster
Chemical equilibrium definition:
Dynamic chemical equilibrium refers to a reversible reaction in which the forward and the reverse
reactions are taking place at the same rate, and hence the concentration of the reactants and products
are constant.
LE CHATELIER'S PRINCIPLE
When an external stress (change in pressure, temperature or concentration) is applied to a system in
dynamic chemical equilibrium, the equilibrium point will change in such a way as to counteract the
stress.
How do we explain an equilibrium shift using LeChatelier'sprinciple LCP
D state thedisturbance egaddingwater
O statehowthesystemopposes thedisturbancebyLCP egsystemtriestoabsorb
excess water
F state which reaction is favoured Fwd productsmade ns reactantsmade
R Reporton theresult eg productsaremade pinkionsaremadeetc
, Example go.EU ii6Hao gqitioji Ha oHco exothermic
iTheforwardreactionisexothermic
reversereactionisendothermic
IaterSaddd the bluecobaltchloride code ions theequilibriumshiftsrightandthe
forward reactionis favoured Thesolutionturnspink becausecobalt water H2O ionsaremade
D waterisadded to the system
molecules
O ByLCP thesystemusesupthe excess water
F The forward reaction is favoured
ions aremade
R Pinkcobaltwater coH2o
If concentrated HCl isadded
causesthereversereactionto be favoured touseuptheexcess Ctions bluecobaltchlorideionsare
formed as a result
D HCl ie c ions areadded
O ByLCP thesystemtries to use up the ce ions
F Reverse reaction is favoured
R Blue cobalt chloride coat ions are made
Ifsolutionisheated
Heatinga solutionalwaysfavourstheendothermicreactiontoabsorbtheheatThusthereversereaction
inthissolution isfavoured
D thesystem is heated
O ByLCP thesystemfavours the endothermicreaction totryand cool itself
down absorb the excess heatenergy
F Thereverse reaction is favoured
R Bluecobaltchloride Cody ions aremade
, Ifsolutioniscoded
coolingasolutionalwaysfavours the exothermicreaction togiveoffheatinorderto warmitselfup
againThustheforwardreactioninthissolutionis favoured
D thesystemiscooled
thesystemfavourstheexothermicreaction to tryheat itself up
ByLCP excess
O release heatenergy
F theforwardreaction is favoured
Pinkcobalt water CoH2OG ions aremade
R
reactionisreversible
Ticalhanger Fance eathhmical
reactionhas anatural
equilibrium point
I
Forwardreaction y AB whenfudreactionisfavoured
equilibriumshiftsright
Reversereaction ATB Y whenns reactionisfavoured
equilibriumshiftsleft
CHEMICAL EQUILIBRIUM RATESOFREACTION
ensuresthattheamountofproduct reactant
Theratesofthe forward reversereactionsareequalatequilibrium sidewillremainthesame
oneither
scientistscanmanipulatetherateofreactiontoreachequilibriumfaster
Chemical equilibrium definition:
Dynamic chemical equilibrium refers to a reversible reaction in which the forward and the reverse
reactions are taking place at the same rate, and hence the concentration of the reactants and products
are constant.
LE CHATELIER'S PRINCIPLE
When an external stress (change in pressure, temperature or concentration) is applied to a system in
dynamic chemical equilibrium, the equilibrium point will change in such a way as to counteract the
stress.
How do we explain an equilibrium shift using LeChatelier'sprinciple LCP
D state thedisturbance egaddingwater
O statehowthesystemopposes thedisturbancebyLCP egsystemtriestoabsorb
excess water
F state which reaction is favoured Fwd productsmade ns reactantsmade
R Reporton theresult eg productsaremade pinkionsaremadeetc
, Example go.EU ii6Hao gqitioji Ha oHco exothermic
iTheforwardreactionisexothermic
reversereactionisendothermic
IaterSaddd the bluecobaltchloride code ions theequilibriumshiftsrightandthe
forward reactionis favoured Thesolutionturnspink becausecobalt water H2O ionsaremade
D waterisadded to the system
molecules
O ByLCP thesystemusesupthe excess water
F The forward reaction is favoured
ions aremade
R Pinkcobaltwater coH2o
If concentrated HCl isadded
causesthereversereactionto be favoured touseuptheexcess Ctions bluecobaltchlorideionsare
formed as a result
D HCl ie c ions areadded
O ByLCP thesystemtries to use up the ce ions
F Reverse reaction is favoured
R Blue cobalt chloride coat ions are made
Ifsolutionisheated
Heatinga solutionalwaysfavourstheendothermicreactiontoabsorbtheheatThusthereversereaction
inthissolution isfavoured
D thesystem is heated
O ByLCP thesystemfavours the endothermicreaction totryand cool itself
down absorb the excess heatenergy
F Thereverse reaction is favoured
R Bluecobaltchloride Cody ions aremade
, Ifsolutioniscoded
coolingasolutionalwaysfavours the exothermicreaction togiveoffheatinorderto warmitselfup
againThustheforwardreactioninthissolutionis favoured
D thesystemiscooled
thesystemfavourstheexothermicreaction to tryheat itself up
ByLCP excess
O release heatenergy
F theforwardreaction is favoured
Pinkcobalt water CoH2OG ions aremade
R
