On this problem I keep getting the wrong answer. I am subtracting the initial concentration of Cl2 by the equilibrium concentration then using the difference to subtract for the rest using the mole ratios. Then i used the keq constant equation of concentration of products over reactants but i still got the wring answer.

The initial concentration for the compounds involved in the reaction displayed were determined to be [Br2(g)] = 0.3864 mol/L, [Cl2(g)] = 0.5011 mol/L, [BrCl(g)] = 0.06735 mol/L. Calculate the value of the equilibrium constant (Kc) at 227.0 °C if the equilibrium concentration of Cl2(g) was 0.4965 mol/L.

Br2(g)+Cl2(g) = 2BrCl(g)

If you had posted your work I could have found the error. As it stands I can't. I obtained 0.01784 for Kc.

To calculate the equilibrium constant (Kc) at a given temperature, you can use the law of mass action. The equilibrium constant expression is given by:

Kc = ([BrCl]^2) / ([Br2] * [Cl2])

where [BrCl], [Br2], and [Cl2] represent the equilibrium concentrations of BrCl(g), Br2(g), and Cl2(g) respectively.

Given the initial concentrations and equilibrium concentration of Cl2, you can substitute these values into the equation to find Kc.

Let's calculate step by step:

Step 1: Substitute the values into the equilibrium constant expression:
Kc = ([BrCl]^2) / ([Br2] * [Cl2])
Kc = (0.06735^2) / ([Br2] * 0.4965)

Step 2: Rearrange the equation to solve for [Br2]:
[Br2] = (0.06735^2) / (Kc * 0.4965)

Step 3: Now we need to determine the equilibrium concentration of Br2, which can be calculated using the initial concentration of Br2 and the change in concentration due to the reaction. The balanced equation tells us that 1 mol of Br2 reacts to form 2 mol of BrCl. Therefore, the equilibrium concentration of Br2 will be:

[Br2]eq = [Br2]initial - (2 * [BrCl]eq)

Step 4: Substitute the values into the equation:
[Br2]eq = 0.3864 - (2 * 0.06735)

Step 5: Calculate the equilibrium constant:
Kc = (0.06735^2) / ([Br2]eq * 0.4965)

Now you can plug in the values you obtained into the equation to calculate the equilibrium constant (Kc). Make sure to double-check your calculations to ensure accuracy.

If you have already followed these steps and obtained a different answer, please double-check your calculations and ensure that you substituted the correct values into the equations.