When 1.00 mol of A and 0.800 mol of B are placed in a 2.00 L container and allowed to come to equilibrium, the resulting mixture is found to be 0.20M in D. What is the value of K at equilibrium?
You can't solve this without knowing the equation.
A + 2B => D or
2A + B = 2D or
etc.
2A (aq) + B (aq) <-> C (g) + D (g)
(A) = 1 mol/2L = 0.500M
(B) = 0.800/2 = 0.400 M
,,,,,,,,,,,,,,,,,,,,,,2A (aq) + B (aq) <-> C (g) + D (g)
I.....................0.5.........0.4...............0.........0
C,,,,,,,,,,,,,,,,,,,,-2x.........-x...............+x........+x
E.................0.5-2x......0.4-x.............x..........x
The problems tells you that x = 0.20M.
Write the K expression for the reaction, plug in the values for A, B, C, D, and solve for K. Post your work if you get stuck.
What is the k expression?
Keq = (concn of right side)^coefficients/(concn left side)^coeff or
Keq = (C)(D)/(A)^2(B)
To find the value of K, we need to set up an equilibrium expression and substitute the given information into it. The equilibrium expression for the reaction is:
K = [D]^x/[A]^a[B]^b
where [D], [A], and [B] represent the molar concentrations of D, A, and B at equilibrium, and x, a, and b are the coefficients of D, A, and B in the balanced equation, respectively.
Let's assume that the balanced equation for the reaction is:
A + B -> D
According to the given conditions, 1.00 mol of A and 0.800 mol of B are placed in a 2.00 L container. To calculate the molar concentration of D at equilibrium, we need to determine the amount of D produced.
Since 1.00 mol of A and 0.800 mol of B are consumed in the reaction, the moles of D formed will be equal to the lesser of the two reactants, which is 0.800 mol.
The given mixture is also 0.20 M in D. Molar concentration (M) is calculated by dividing the moles of solute by the volume of the solution in liters. In this case, the volume of the solution is 2.00 L.
Therefore, the molar concentration of D at equilibrium can be calculated as follows:
[D] = moles of D / volume of the solution
= 0.800 mol / 2.00 L
= 0.400 M
Now we can substitute the molar concentrations into the equilibrium expression:
K = [D]^x/[A]^a[B]^b
K = (0.400 M)^x / (1.00 M)^a * (0.800 M)^b
Since we don't know the coefficients x, a, and b, we cannot calculate the exact value of K at equilibrium without additional information about the balanced equation. The value of K will depend on the stoichiometry of the reaction.