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 reaction2COF2(g)⇌CO2(g)+CF4(g), Kc=5.70If only COF2 is present initially at a concentration of 2.00 M, what concentration of COF2 remains at equilibrium?

[COF₂] = 0.346M

Explanation:

For the reaction:

2COF₂(g) ⇌ CO₂(g) + CF₄(g)

Kc = 5.70 is defined as:

Kc = [CO₂] [CF₄] / [COF₂]² = 5.70 (1)

Equilibrium concentrations of each compound after addition of 2.00M COF₂ will be:

[COF₂] : 2.00M - 2x

[CO₂] : x

[CF₄] : x

Replacing in (1):

5.70 =  [X] [X] / [2-2x]²

22.8 - 45.6x + 22.8x² = x²

0 = -21.8x² + 45.6x - 22.8

Solving for x:

X = 1.265 -False answer, will produce negative concentrations-

X = 0.827.

Replaing, molar concentration of COF₂ is:

[COF₂] : 2.00M - 2×0.827 = 0.346M

I hope it helps!

the answer is definitely c.