Chemical Thermodynamics Unit 14: Chemical Thermodynamics Dr. Jorge L. Alonso Miami-Dade College –...

ChemicalThermodynamics

Unit 14Chemical

Thermodynamics

Dr Jorge L AlonsoMiami-Dade College ndash Kendall Campus

Miami FL

Textbook Reference bullChapter 15 (sec12-17)

bullModule 3 (sec VIII-XII)

CHM 1046 General Chemistry and Qualitative Analysis


First Law of Thermodynamics

bull The law of conservation of energy energy cannot be created nor destroyed (James Joule in 1843 )

E = q + ww = PV

E = q + PVE = q + RT

Esys + Esurr = 0

Esys = -Esurr

bull Therefore the total energy of the universe is a constant

bull Energy can however be converted from one form to another or transferred from a system to the surroundings or vice versa


Second Law of Thermodynamics

Do all processes that loose energy occur

spontaneously (by themselves without

external influence)

First Law of ThermodynamicsStoneE1

E2

E = E2 ndash E1

Spontaneity

+ Work

- (work + heat)


Spontaneous Processesbull can proceed without any outside intervention

Spontaneity

Processes that are spontaneous in one direction

are nonspontaneous

in the reverse direction


Spontaneous Processesbull Processes that are spontaneous at one temperature

may be nonspontaneous at other temperaturesbull Above 0C it is spontaneous for ice to meltbull Below 0C the reverse process is spontaneous

Is the spontaneity of

melting ice dependent on

anything

Spontaneous T gt 0ordmC

Spontaneous T lt 0ordmC


Spontaneity

Thermodynamics vs Kinetics

C diamond C graphite

vs Speed


Stone

+ Work

Irreversible Processes

bull Heat energy is lost to dissipation and that energy will not be recoverable if the process is reversed

bull Irreversible processes cannot be undone by exactly reversing the change to the system

bull Spontaneous processes are irreversible

In a reversible process the system changes in such a way that the system and surroundings can be put back in their original states by exactly reversing the process

E1

E2

- (work + heat)

Reversible Processes


Entropy (S)

bull Entropy (S) is a term coined by Rudolph Clausius in the 1850rsquos Clausius chose S in honor of Sadi Carnot (who gave the first successful theoretical account of heat engines now known as the Carnot cycle thereby laying the foundations of the second law of thermodynamics)

bull Clausius was convinced of the significance of the ratio of heat delivered and the temperature at which it is delivered

qT

Entropy (S) =

Entropy is a measure of the energy that becomes dissipated and unavailable (friction molecular motion = heat)


Entropy (S)bull Entropy can be thought of

as a measure of the randomness (disorder) of a system

bull It is related to the various modes of motion in molecules

EntropyWaterBoiling

bull Like total energy E and enthalpy H entropy is a state function

bull Therefore

S = Sfinal Sinitial Solid

Liquid

Gas

ENTROPY



bull the entropy of the universe increases for spontaneous (irreversible) processes

bull the entropy of the universe does not change for reversible processes

Suniv = Ssystem + Ssurroundings gt 0

Suniv = Ssystem + Ssurroundings = 0



All spontaneous processes cause the entropy of the universe to increase

ENTROPIC DOOMENTROPIC DOOM

So what is our fate as a result of the second law operating in our Universe


Entropy on the Molecular Scalebull Molecules exhibit several types of motion (Kinetic energies)

Translational Movement of a molecule from one place to another Vibrational Periodic motion of atoms within a molecule Rotational Rotation of the molecule on about an axis or rotation about

bonds

bull Boltzmann envisioned the motions of a sample of molecules at a particular instant in time This would be akin to taking a snapshot of all the

molecules He referred to this sampling as a microstate (W) of the

thermodynamic system

bull Entropy is helliphellip

S = k ln W

hellipwhere k is the Boltzmann constant 138 1023 JK


Entropy on the Molecular Scale

bull The number of microstates (W) and therefore the entropy (S) tends to increase with increases in which variableshellip

Temperature (T)

Volume (V)

The number of independently moving molecules ()

S = k ln W



Entropy Changes

CaCl2 (s) Ca 2+(aq) + 2Cl-(aq)

H2O

H2O (l) H2O(g)Heat

2 H2O (l) 2 H2 (g) + O2(g)Electricity

16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18

bull In which of the following does Entropy increase amp WHYhelliphellipGases are formed from liquids and solids

Liquids or solutions are formed from solids

The number of gas molecules (or moles) increases

EntropySolutionsKMnO4(aq)

EntropyampPhaseOfMatter

bull Entropy increases with the freedom of motion of molecules

S(g) gt S(l) gt S(s)


Third Law of Thermodynamics

The entropy (S) of a pure crystalline substance at absolute zero (-273degC) is 0


Standard Entropiesbull Standard entropies tend to increase with increasing

molar mass

bull Larger and more complex molecules have greater entropies (greater ways to execute molecular motions)

EntropyampMolecuarSize EntropyampTempC7H15 500 K S=921JnK vs 200 K


Absolute Entropy (S)

- 237degC (0 K) S = 0

Standard Entropy (S˚)

25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S

Calculate the sum of all the infinitesimally small changes in entropy as T varies from T=0 T= 298 by taking its Integral

Standard Entropies (298 K) from Absolute Entropies (0K)

Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S


Entropy Changes in the System

where n and m are the coefficients in the balanced chemical equation

o

reactants

o

products

o

298 SmSnS

Sdegsyst = Sdegrxn T

Entropy changes for a reaction (= system) can be estimated in a manner analogous to that by which H is estimated


Problem Calculate the standard entropy changes for the following reaction at 25oC

N2 (g) + 3 H2 (g) 2 NH3 (g)

Sdeg = nSdeg(prod) - mSdeg(react)

Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S

Thermodynamic Changes in Systems (Chem Reactions)

Appendix 1 (CHM 1046 Module) notice Sdeg is in J not kJ

Grxn = Gf (products) Gf (reactants)

Hrxn = Hf (products) - Hf (reactants)


Entropy Changes in the Surroundings

bull Heat (q) that flows into or out of the system changes the entropy of the surroundings

Ssurr prop - (qsys)

bull For an isothermal process

Ssurr= (qsys)

Tbull At constant pressure qsys is

simply H for the system

System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings

What in a chemical reaction causes entropy changes in the surroundings


Entropy Change in the Universe

K 298

1000 692( kJ) Jxmol kJ

Problem Calculate the Suniv for the synthesis of ammonia 25oC

N2 (g) + 3 H2 (g) 2 NH3 (g) Hdegrxn = - 926 kJmol

Ssurr =-Hsys

T

Ssurr = 311 JKmol

Suniv = Ssyst or rxn + Ssurr

nS(prod) - mS(react)

Sdegsyst = - 199 JKmiddotmol

2(1925) ndash [(1915)+3(1306)]

Suniv = - 1983 JKmiddotmol + 311 JKmol

Suniv = 113 JKmol



bull Then

Suniv = Ssyst + Hsystem

T


Ssurr =-Hsys

Tbull Since

TSuniv = Hsyst TSsyst

TSuniv is defined as the Gibbs (free) Energy G

TSuniv = TSsyst + Hsyst

J Willard Gibbs USA 1839-1903

Multiplying both sides by T


bull When Suniv is positive G is negative

bull When G is negative the process is spontaneous

Gibbs Free Energy (G)

Gibbs Energy (-TΔS) measures the useful or process-initiating work obtainable from an isothermal isobaric thermodynamic system Technically the Gibbs free energy is the maximum amount of non-expansion work which can be extracted from a closed system or this maximum can be attained only in a completely reversible process

Guniv = Hsys TSsysTSuniv =


Free Energy Changes

At temperatures other than 25degC

Gdeg = H TS

How does G change with temperature

bull There are two parts to the free energy equation Hmdash the enthalpy term TS mdash the entropy term

bull The temperature dependence of free energy then comes from the entropy term


Spontaneity Enthalpy amp Entropy

Gdeg = H TS

Spontaneous all T

NonSpontaneous all T

Spontaneous high T

Spontaneous low T



Entropy Driven Reactions

Entropy amp Enthalpy Driven Reaction

Enthalpy Driven Reaction

Na2CO3(s) + HCl(aq) NaCl(aq) + CO2 (g)

2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)

EntropySyst+SurrFormationOfWater

(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O


ProblemsGdeg = HT(S)

(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product


Standard Free Energy Changes

Analogous to standard enthalpies of formation are standard free energies of formation G

f

G = nG(products) mGf (reactants)f

where n and m are the stoichiometric coefficients



12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)

Grxn = nG(prod) mG(react)f

Calculate the standard free energy changes for the above reaction 25 degC

f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]

ndash [2 C6H6 (l) + 15 O2(g)][12 CO2(g) + 6 H2O(g)]

Grxn = - 6352 Jmol K

Standard Molar Gibbs Energy of Formation (Gdegf)

CO2 (g) -394

H2O (g) -229

C6H6 (l) 125


Fourth Law of Thermodynamics EmergenceComplex emergent systems spontaneously (-G) arise when energy flows through a collection of many interacting particles resulting in new patterns of complex behaviors that are much more than the sum of the individual parts (+S)

The formation of these complex patterns in emergent systems is more efficient in the dissipation of energy (-H) thus speeds up the increase of entropy in the universe

G = H -TSA precise definition of emergence and a useful mathematical formulation of this phenomenon remains elusive

C f [n i E(t)]Examples cells forming living organisms stars forming galaxies neurons forming conscious brain








2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




First Law of Thermodynamics

bull The law of conservation of energy energy cannot be created nor destroyed (James Joule in 1843 )

E = q + ww = PV

E = q + PVE = q + RT

Esys + Esurr = 0

Esys = -Esurr

bull Therefore the total energy of the universe is a constant

bull Energy can however be converted from one form to another or transferred from a system to the surroundings or vice versa





external influence)


E2

E = E2 ndash E1

Spontaneity

+ Work

- (work + heat)



Spontaneity


are nonspontaneous







anything




Spontaneity



vs Speed


Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)







external influence)


E2

E = E2 ndash E1

Spontaneity

+ Work

- (work + heat)



Spontaneity


are nonspontaneous







anything




Spontaneity



vs Speed


Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





Spontaneity


are nonspontaneous







anything




Spontaneity



vs Speed


Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)








anything




Spontaneity



vs Speed


Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




Spontaneity



vs Speed


Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




Stone

+ Work






E1

E2

- (work + heat)



Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




Entropy (S)



qT

Entropy (S) =






EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)







EntropyWaterBoiling


bull Therefore


Liquid

Gas

ENTROPY















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)

















bonds





S = k ln W





Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)






Temperature (T)

Volume (V)


S = k ln W



Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




Entropy Changes


H2O

H2O (l) H2O(g)Heat


16 CO2(g) + 18 H2O(g)2 C8H18 (l) + 25 O2 (g)

gas= 34-25 = +92 = 45 C8H18













molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)








molar mass





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





- 237degC (0 K) S = 0


25degC (298 K) S =

dT298

0 T

C

T

TCS

K 298T

0T

T

TC

T

Tmc

T

q S



Sdeg

Temp (K)

Solid Liquid Gas

Hdegfus

Hdegvap

q = mcT

q = mcT

q = mcT

298

S




o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)






o

reactants

o

products

o

298 SmSnS





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





N2 (g) + 3 H2 (g) 2 NH3 (g)


Sdeg = - 1983 J

2(1925) ndash [(1915)+3(1306)]



oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)




oreactants

oproducts

o298 S S S








Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)






Ssurr prop - (qsys)


Ssurr= (qsys)



System

q

q

qq

q

q

q

Ssurr= Hsys

TSurroundings




K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





K 298




Ssurr =-Hsys

T

Ssurr = 311 JKmol




2(1925) ndash [(1915)+3(1306)]


Suniv = 113 JKmol



bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





bull Then


T


Ssurr =-Hsys

Tbull Since













Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)










Free Energy Changes


Gdeg = H TS






Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





Gdeg = H TS

Spontaneous all T


Spontaneous high T

Spontaneous low T







2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)









2 H2(g) + O2 (g) 2 H2O(g)

NH4NO3(s) NH4+

(aq) + NO3-(aq)

n = 2-3 = -1

S = +H = +

G = H( TS)


(-TS)

(-TS)

(+TS)H = - S = -

H = - S = +

Enthalpy EntropyH2O



(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





(-763)

ndash (-804)

+41

(3549)

ndash (2219)

+1330

Gdeg = H TS = (1313kJ) T(133kJ)

T = 987

TiCl4(l) TiCl4(g)

(-T)Reactant

Product




f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)






f





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





12 CO2(g) + 6 H2O(g)2 C6H6 (l) + 15 O2 (g)



f

[12(-394) + 6(-229)] ndash [2(125) + 15 (0)]




CO2 (g) -394

H2O (g) -229

C6H6 (l) 125













2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)















2002 B




2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)






2003 A



2004 A




2004 B



2005 A



2006 (B)




2007 (A)





2004 A




2004 B



2005 A



2006 (B)




2007 (A)






2004 B



2005 A



2006 (B)




2007 (A)





2005 A



2006 (B)




2007 (A)





2006 (B)




2007 (A)






2007 (A)



Chemical Thermodynamics Unit 14: Chemical Thermodynamics Dr. Jorge L. Alonso Miami-Dade College –...

Documents

Transcript of Chemical Thermodynamics Unit 14: Chemical Thermodynamics Dr. Jorge L. Alonso Miami-Dade College –...