Predict the direction a reaction will go,
given any reaction conditions.
At 298 K, N2, H2, and NH3 are combined, each with
partial pressures of 0.5 atm. Which direction does the
reaction go? Support your results with a quantitative
calculation.
Kp at 298 K is 6.8 × 105.
Relate K expressions and values for
related chemical equations
Ammonia gas decomposes to nitrogen and
hydrogen gas at 298 K. What is the Kp for the
reaction and which side of the decomposition
equation is favored at equilibrium?
Relate Kc to Kp for gas phase reactions
What is the Kc for the above decomposition
reaction?
Calculate equilibrium concentrations or
partial pressures, given Kc or Kp and
initial conditions
A mixture of N2 and H2 is prepared with
concentrations of 0.020 M N2 and 0.010 M H2,
with no ammonia. Calculate the equilibrium
concentration of NH3, assuming that it is small
compared to the initial concentrations of N2 and
H2. Be sure to check the validity of your
approximation.
Calculate K for
C (graphite)
£ C (diamond)
Use your previous value of ∆G°.
What does the sign of ∆G° tell you about
spontaneity?
What does the value of K tell you about the
relative amounts of graphite and diamond at
equilibrium? What can you say about
spontaneity for this reaction?
Calculate K from thermodynamic info
C (graphite)
£ C (diamond)
Calculate ∆H°, ∆S°, and ∆G°.
How do entropy and enthalpy contribute to
∆G°?
Which form of carbon is thermodynamically
more stable?
Calculate K for the reaction, from your above
results.
What does the value of K tell you about the
relative amounts of graphite and diamond at
equilibrium?