For the equilibrium PCl5(g)⇌PCl3(g)+Cl2(g), the equilibrium constant Kp is 0.497 at 500K. A gas cylinder at 500K is charged with PCl5(g) at an initial pressure of 1.66atm. Determine the equilibrium pressure of all species at this temperature.

Explanation:

Hello,

In this case, for the given reaction, the equilibrium expression is:

But in terms of the reaction extent can also be written as:

Whereas the initial pressure is 1.66 atm. Thus, we write:

And solving for we obtain:

Therefore, the pressure of each species at equilibrium is:

Best regards.

c is the answer because when something is left after something evaporates that shows the chemical change.