Equilibrium Flashcards
(21 cards)
Conditions required for equilibrium?
Closed system
Macroscopic properties remain constant
Evidence of reversibility
2 types of equilibrium?
Static-no small adjustments made once equil’b is reached
Dynamic- constant adjustments made in order to maintain equilibrium
3 types of Dynamic Equilibrium
Phase (rate of evaporation=rate of condensation)
Solubility (forward rxn initially greater, rate of dissolving=rate of crystallization)
Chemical (forward rxn=reverse rxn)
Formula for %reaction
%rxn = what u have/what u could hav
Formula for Kc
Kc =product/reactant
Gaseous/aqueous sol’ns, temp remains constant
Factors affecting rxn rate
Concentration
Pressure
Temperature
Catalysts
Kc is greater than 1/ % yield is >50%
Products favored
Kc is <50%
Reactants favoured
Increace pressure
Shift to less moles (gasses only)
Decrease pressure
More moles (gasses only)
Equal numbers of moles of reactants & products?
No shift
Catalyst
Doesnt change Kc
Speeds up forward & reverse rxn
Shortens time to reach equilibrium
Haber process?
Chemically fixed N2 with NH3
Used 200 atm, 600*C, uranium & osmium catalysts
Only thing worked was removing NH3 itself as it was produced
Graphing changes in Equil’b
A) concentration
B) pressure
C) temperature
A) only ONE has a distinct line
B) ALL have distinct lines
C) NO distinct lines
Kw = ?
Kw = 1.0 x 10-14
Significant Digits rule for pH & pOH?
Only count AFTER the decimal
%yield equation?
[H+]. x100
[acid]
Ka equation?
[H+]2
[acid]
Kb equation?
[OH]2
[base]
Second Kb equation?
Kb = Kw/Ka
Kc for reverse rxn?
1/Kc (forward rxn)
