Equilibria Flashcards
two features of dynamic equilibrium
forward and backwards reactions occur at the same rates
concnetrations of products and reactants is constant
Le Chateleir’s principle
if an external condition is changed equilibrium will shift to oppose the change
at increased temperatures eqm will…
equilibrium will shift to favour the endothermic reaction
at higher pressure eqm will…
the equilibrium will shift towards the side with fewer moles of gas
what is a negative about industrially high pressures
high electical costs for pumping mechanism and equipment is expensive
effect of catalyst on equilibrium
no effect as it speeds up the rate of forward and backward reactions by the same amount
production of ammonia equation and conditions
(Haber process)
N2 + 3H2 <—–> 2NH3
450 degrees C
200-1000 atm
iron catalyst
production of methanol equation
CO(g) + 2H2(g) <——-> C3OH(g)
Kc equation for reaction
mA + nB <——-> pC + qD
Kc = [C]^p x [D]^q
——————–
[A]^m x [B]^n
effect of Kc if there are fewer products
Kc gets smaller
Contact process (making SO3)
S + O2 ——> SO2
2SO2 + O2 <——-> SO3
exothermic
450 degrees C
1-2atm
V2O5 catalyst
hydration of ethene eqn and conditions
CH2=CH2 = H2O <——> CH3CH2OH
H3PO4 catalyst (conc.)
300 degrees C
70atm
high pressure used to avoid the formation of (poly)ethene
carbon neutral meaning
no net carbon emissions to the atmosphere
what must you use to work out Kc
moles AT EQUILIBRIUM
what causes Kc to change
ONLY temperature
how to work out equilibrium constant for esterification reaction
add ethanoic acid and ethanol in a test tube with sulfuric acid catalyst
leave for a week so they can equilibriate
titrate with NaOH
this will tell you the total mol of H+
how to ensure that equilibrium has been reached
leave solutions for different amounts of time. When concentrations are constant then eqm. has been reached.
what is partial pressure
the pressure of a gas if it alone would occupy the whole space
total pressure is equal to
partial pressures combined
partial pressure is equal to
mol fraction x total pressure
Kp equation for reaction
mA + nB <——-> dC + qD
Kp = p(C)^d x p(D)^q
——————–
p(A)^m x p(B)^n
