Question

Part A

Carbonyl fluoride, COF2, is an important intermediate used in the production of fluorine-containing compounds. For instance, it is used to make the refrigerant carbon tetrafluoride, CF4 via the reaction

2COF2(g)⇌CO2(g)+CF4(g),    K=7.80 at 850 K

If only COF2 is present initially at a pressure of 246 kPa, what is the partial pressure of COF2 at equilibrium?

You can convert the units of pressure from kPa to bar, using the relation 1 kPa=0.01 bar.

Part B

Consider the reaction

CO(g)+NH3(g)⇌HCONH2(g),    K=2.70 at 550 K

If a reaction vessel initially contains only CO and NH3 at partial pressures of 2.40 bar and 1.60 bar, respectively, what will the partial pressure of HCONH2 be at equilibrium?

Answer 1

A)

Initial Pressure of COF2 = 246 kPa

Reaction: 2COF2(g)⇌CO2(g)+CF4(g)

Initial: .......246 ..............0............0

Change: ..-2p .............+p..........+p

Final:.....246-2p..........p..............p

Kp = p * p / (246 - 2p)

=> 7.8 = p * p / (246 - 2p)

=> p = 36.7 kPa

Total Pressure at equilibrium = 246 - 2p + p + p = 246 kPa

Partial Pressure of COF2 = 246 - 2p = 172.6 kPa

B)

Reaction: CO(g)+NH3(g)⇌HCONH2(g)

Initial:.......2.4 .... 1.6 ..............0

Change: -p .......-p..................p

Final: ...2.4-p....1.6-p.............p

Kp = 2.7 = p / (2.4-p) * (1.6-p)

=> p = 1.218 kPa

Partial Pressure of HCON2 = p = 1.218 kPa