A student ran the following reaction in the laboratory at 327 K:
CH4(g) + CCl4(g) 2 CH2Cl2(g)
When she introduced 4.07E-2 moles of CH4(g) and 7.57E-2 moles of CCl4(g) into a 1.00 Liter container, she found the equilibrium concentration of CH2Cl2(g) to be 1.21E-2 M.
Calculate the equilibrium constant, Kc, she obtained for this reaction.
I suggest you find and use the arrow key. Since the volume is 1L, the # mols = concn in M.
.......CH4(g) + CCl4(g)==> 2 CH2Cl2(g)
I.....0.0407....0.0757.........0
C.......-x.........-x.........2x
E......0.0407-x..0.0757-x.....2x
The problem tells you 2x = 0.0121M
That allows you to calculate the E line for each constituent. Substitute those values into Kc expression and solve for Kc. Post your work if you get stuck.
To calculate the equilibrium constant, we need to use the equation:
Kc = ([CH2Cl2]^2) / ([CH4] * [CCl4])
First, we need to find the concentrations of CH4 and CCl4 at equilibrium. Since the initial moles and volume are given, we can calculate the initial concentrations:
[CH4] = (4.07E-2 moles) / (1.00 L) = 4.07E-2 M
[CCl4] = (7.57E-2 moles) / (1.00 L) = 7.57E-2 M
Next, we can use the equilibrium concentration of CH2Cl2 to find its molar concentration:
[CH2Cl2] = 1.21E-2 M
Now we can substitute these values into the equation for the equilibrium constant:
Kc = ([CH2Cl2]^2) / ([CH4] * [CCl4])
= (1.21E-2 M)^2 / (4.07E-2 M * 7.57E-2 M)
Kc = 1.21E-4 / (3.08E-3 * 5.86E-3)
= 1.21E-4 / 1.8E-5
Kc = 6.72
Therefore, the equilibrium constant, Kc, for this reaction is 6.72.
To calculate the equilibrium constant, Kc, for this reaction, we need to use the given initial and equilibrium concentrations.
The balanced chemical equation for the reaction is:
CH4(g) + CCl4(g) -> 2 CH2Cl2(g)
We are given the initial concentrations as:
[CH4] = 4.07E-2 moles / 1.00 L = 4.07E-2 M
[CCl4] = 7.57E-2 moles / 1.00 L = 7.57E-2 M
[CH2Cl2] (equilibrium) = 1.21E-2 M
To calculate the equilibrium constant Kc, we use the following equation:
Kc = ([CH2Cl2]^2) / ([CH4] * [CCl4])
Plugging in the values we have:
Kc = (1.21E-2)^2 / (4.07E-2 * 7.57E-2)
Kc = 0.0147 / 0.0030829
Kc ≈ 4.78
Therefore, the equilibrium constant Kc obtained for this reaction is approximately 4.78.