Enter the concentration of a substance in one medium and the concentration of the same substance in another medium to determine the partition coefficient.

## Partition Coefficient Formula

The following formula is used to calculate a partition coefficient.

Kp = (C1/C2)
• Where Kp is the partition coefficient
• C1 is the concentration of the substance in medium 1 while at equilibrium
• C2 is the concentration of the substance in medium 2 while at equilibrium

To calculate the partition coefficient, divide the concentration in the 1st medium by the concentration in the reference medium, both while at equilibrium.

## Partition Coefficient Definition

What is a partition coefficient? A partition coefficient is a ratio of the concentration of a substance in two different mediums while at equilibrium in both of those mediums.

## Example Problem

How to calculate partition coefficient?

1. First, determine the concentration of the substance in the first medium.

For this example, the first medium is water and the substance is sodium. The concentration in the water is 50 mol/L.

2. Next, determine the concentration of the substance in the second medium.

For this example, the second medium is liquid nitrogen, and the concentration of the sodium is 25 mol/L.

3. Finally, calculate the partition coefficient.

Using the formula above, we calculate the partition coefficient as 50/25 = 2.