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?

**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.

**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.

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