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Chemical Equilibrium

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Submitted By gotaname
Words 327
Pages 2
Terms
Hemoglobin
Fetal Hemoglobin
Dynamic Equilibrium – when rates of forward and reverse reactions are equal, rendering static concentration(s) of reactants and products
Kc – Equilibrium constant with respect to concentration in molarity (M)
Kp – Equilibrium constant with respect to partial pressures in atmospheres
Equilibrium constant – ratio of concentration of products raised to their stoichiometric coefficients divided by reactants raised to their stoichiometric coefficients (reaction quotient)
Heterogeneous equilibrium
Reaction quotient
Le Châtelier’s Principle

Concepts
Law of Mass Action when aA+bB↔cC+dD Kc=CcDdAaBb

when A↔2B, K1=B2A when 2B↔3C, K2=C3B2 A↔2B2B↔3CA↔3C Koverall=C3A

nA+2nB↔3nC therefore K'=C3nAnB2n=Kn
Heterogeneous reactions – concentrations of pure solids (s) are constant; both pure solids and pure liquids (l) are excluded from equilibrium expression

Calculations
Equilibrium constant K=CcDdAaBb

Equilibrium equation A+2B↔3C, therefore…

Kforward=C3AB2 Kreverse=AB2C3 Kreverse=1Kforward

Kc=CcDdAaBb

PA=ART eq 14.1

Kp=Kc(RT)∆n eq. 14.2

Key Tables/Figures:

Table 14.1 Initial and Equilibrium Concentrations for the Reaction H2g+I2g↔2HIg at 445°C Initial | Equilibrium | Equilibrium Constant | H2
H2
| | I2
I2
| | HI
HI
| | 0.50 | 0.50 | 0.0 | 0.0 | 0.0 | 0.50 | 0.50 | 0.50 | 0.50 | 1.0 | 0.50 | 0.0 | 0.50 | 1.0 | 0.0 | | H2
H2
| | I2
I2
| | HI
HI
| | 0.11 | 0.11 | 0.78 | 0.055 | 0.055 | 0.39 | 0.165 | 0.165 | 1.17 | 0.53 | 0.033 | 0.934 | 0.033 | 0.53 | 0.934 | | Kc=HI2H2I2
Kc=HI2H2I2
| | 0.782(.011)(0.11)=50
0.782(.011)(0.11)=50
0.392(0.055)(0.055)=50
0.392(0.055)(0.055)=50
| | 1.172(0.165)(0.165)=50
1.172(0.165)(0.165)=50
| | 0.9342(0.53)(0.033)=50
0.9342(0.53)(0.033)=50
| | 0.9342(0.033)(0.53)=50
0.9342(0.033)(0.53)=50
| | | | |

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