Question

If the initial concentrations in the bag are [PL] = 0, [L]=0, [P]=4 and the surroundings are [PL]=0, [L] = 12 and [P] = 0, what is the Kd given that equilibrium of left is [PL] = 2, [L)=5, [P] = 2, and right is [PL]=0, [L]=5 and [P]=0?

a) 0.4
b) 1.0
c) 2.0
d) 5.0

Answer 1

The dissociation constant (Kd) for the given equilibrium concentrations is calculated using the formula Kd = [P][L] / [PL], which equals 5.0. This matches option d).

Step-by-step explanation:

To find the dissociation constant (Kd), we need to understand that Kd is the equilibrium constant for the dissociation of the complex PL into P and L. We use the concentrations of these substances at equilibrium to calculate Kd. Using the equilibrium concentrations provided, PL = 2, L = 5, and P = 2, the equation for Kd in this scenario is:

Kd = [P][L] / [PL] = (2)(5) / 2 = 5

Therefore, Kd is 5.0, which corresponds to answer option d).