Equilibrium Flashcards
5 characteristics of an equilibrium state
mdRcs
1. mom - macroscopic properties are constant (temp, pressure, color…)
2. dad - equi can be attained from all direcetions
3. Rony - rate of –> rxn = rate of <– rxn
4. can’t - closed system
5. swim - all species in chem rxn are present in equi rxn
kc smaller than 1
reactants favored
kc bigger than 1
products favored
[R] conc increases
equi shifts to right (product side) to use up reactants added
[p] conc increases
equi shifts to left to use up products added
how is pressure changed
1) adding/removing reactants or products
2) changing volume of vessel
pressure increases
shifts to the side with greater amount of gaseous molecules
pressure decreases
shifts to side with fewest amount of gaseous molecules
exothermic rxn delta H =?
negative - bc heat is exiting therefore -ve
endothermic rxn delta H =?
positive - bc heat is entering the system
temperature increases (exothermic)
equilibrium shifts to the left and the Kc is reduced
temperature decreases (exothermic)
equilibrium shifts to the right and Kc increases
temperature increases (endothermic)
equilibrium shifts to the right and Kc increases
temperature decreases (endothermic)
equilibrium shifts to the left and Kc decreases
homogenous equilibrium
reactants and products are present in the same phase/state
ICE method
I = initial mol of each
C = change in mol of each
E = equilibrium mol of each
- depends on container, if 1 keep the same but if 10 or smth else divide by it
GFE less than 0
spontaneous and rxn proceeds forwards
GFE more than 0
non-spon and rxn proceeds backwards
GFE = 0
@ equilibrium
rearranged version of: ΔG = - RT lnk to find K
k = e^-ΔG/RT
Entropy
degree of disorder in a system, more gaseous moles = more disorder therefore increase therefore positive ΔS
Reaction quotient Q
ratio of products and reactants for a reaction that has not reached equilibrium
