Mcat - Gen Chem Ch. 6

Front 1

Dynamic Equilibrium

Back 1

- involved with reversible reactions which contain forward and reverse reactions

- forward and reverse reactions are going at the same rate

Front 2

Entropy

Back 2

- measure of distribution of energy throughout a system or between a system and its environment

Front 3

Law of mass action

Back 3

- if the systm is at a constant temp, the following ratio is constant

Keq = [C]^c[D]^d/[A]^a[B]^b

Front 4

Equilibrium Constant

Back 4

- For the F and R rxn of 2A--> B+C

- Kc = Keq = [B][C]/[A]^2

Front 5

Reaction Quotient

Back 5

- how to measure the concentrations of all the reactants and products

- concentrations of the products and reactants are not constant

Front 6

Relationships btwn Q and Keq

Back 6

- Q< Keq --> forward rxn has not yet reached equilibrium, greater concen of reactants

- Q = Keq, rxn is in dynamic equilibrium

-Q> Keq --> forward rxn has exceeded equilibrium, greater concen of products

Front 7

Properties of the law of mass action

Back 7

- concentrations of pure solids and liquids do not appear in equil. constant eqns

-Keq = temperature dependent

- Larger the Keq = equilibrium is further to the right

- equil constant for forward rxn = Keq, reverse rxn = 1/Keq

Front 8

Le Chatliers Principle

Back 8

- if stress is applied to a system, the system shifts to relieve that applied stress

Front 9

Ideal Gas Law

Back 9

-if the pressure increases, it will respond by decrease the amount of moles, therefore decreasing the pressure back to equilibrium

Front 10

Volume and Pressure

Back 10

- volume increases, pressure decreases

- system will react by increasing the number of gas moles to restore pressure

Front 11

Changes in temperature (Le Chatliers principle)

Back 11

endothermic: heat = reactant (H>0)

exothermic: heat = product (H<0)

Front 12

Kinetic Product

Back 12

-formed at lower temperatures with smaller heat transfer

- "fast" products: require a lower free energy to form

Front 13

Thermodynamic product

Back 13

- higher temperature with a larger heat transfer

- free energy of the product is lower therefore more stable