In: Chemistry
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), Kc=7.30 If only COF2 is present initially at a concentration of 2.00 M, what concentration of COF2 remains at equilibrium?
[COF2]
[CO2]
[F2]
initial
2.0
0
0
change -2x +1x +1x
equilibrium 2.0-2x +1x +1x
Equilibrium constant expression is
Kc = [CO2]*[F2]/[COF2]^2
7.3 = x^2/(2.0-2x)^2
sqrt(7.3) = x/(2.0-2x)
2.70 = x/(2.0-2x)
5.40 - 5.40*x = x
6.40*x = 5.40
x = 0.844 M
At equilibrium:
[COF2] = 2.0-2x = 2.0-2* 0.844 = 0.312 M
Answer: 0.312 M