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=4.90 if only cof2 is present initially at a concentration of 2.00 m, what concentration of cof2 remains at equilibrium?

Answer : The concentration of remains at equilibrium will be, 0.37 M

Explanation :  Given,

Equilibrium constant = 4.90

Initial concentration of = 2.00 M

The balanced equilibrium reaction is,

Initial conc.    2 M                 0             0

At eqm.         (2-2x) M          x M         x M

The expression of equilibrium constant for the reaction will be:

Now put all the values in this expression, we get :

By solving the term 'x' by quadratic equation, we get two value of 'x'.

Now put the values of 'x' in concentration of remains at equilibrium.

Concentration of remains at equilibrium =

Concentration of remains at equilibrium =

From this we conclude that, the amount of substance can not be negative at equilibrium. So, the value of 'x' which is equal to 1.291 M is not considered.

Therefore, the concentration of remains at equilibrium will be, 0.37 M