Question

For the following reaction, Kc = 255 at 1000 K. CO (g) + Cl2 (g) ⇌ COCl2 (g) A reaction mixture initially contains a CO concentration of 0.1530 M and a Cl2 concentration of 0.177 M at 1000 K.

What is the equilibrium concentration of CO at 1000 K?

What is the equilibrium concentration of Cl2 at 1000 K?

What is the equilibrium concentration of COCl2 at 1000 K?

Answer 1

You start with CO=0.153 and Cl2=0.177

At the equilibrium you will have an amount of COCl2, since the molar ratio of the reactants and products is the same amount of COCl2 at equilibrium is the same amount missing from Cl2 and CO, thus:

At equilibrium

Substituting in the mass action equation:

This yields a second degree equation:

can be solve with the quadratic equation:

X=0.1388

at equilibrium