<u>Answer:</u> The equilibrium concentration of ICl is 0.27 M
<u>Explanation:</u>
We are given:
Initial moles of iodine gas = 0.45 moles
Initial moles of chlorine gas = 0.45 moles
Volume of the flask = 2.0 L
The molarity is calculated by using the equation:

Initial concentration of iodine gas = 
Initial concentration of chlorine gas = 
For the given chemical equation:

As, the initial moles of iodine and chlorine are given. So, the reaction will proceed backwards.
The chemical equation becomes:

<u>Initial:</u> 0.225 0.225
<u>At eqllm:</u> 0.225-x 0.225-x 2x
The expression of
for above equation follows:
![K_c=\frac{[ICl]^2}{[Cl_2][I_2]}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BICl%5D%5E2%7D%7B%5BCl_2%5D%5BI_2%5D%7D)
Putting values in above equation, we get:

Neglecting the value of x = 0.668 because equilibrium concentration cannot be greater than the initial concentration
So, equilibrium concentration of ICl = 2x = (2 × 0.135) = 0.27 M
Hence, the equilibrium concentration of ICl is 0.27 M