Question

The partition coefficient for a solute in chromatography is $\mathbf{K}\mathbf{=}{\mathbf{c}}_{\mathbf{s}}\mathbf{/}{\mathbf{c}}_{\mathbf{m}}$, where ${\mathbf{c}}_{\mathbf{s}}$is the concentration in the stationary phase and ${\mathbf{c}}_{\mathbf{m}}$is the concentration in the mobile phase. The larger the partition coefficient, the longer it takes a solute to be eluted. Explain why.

Short answer

concentration in stationary phase increases there is more concentration that needs to be extracted to the mobile phase and the elution would be longer.

Step-by-step solution

Given Information:

The Partition coefficient for a solute is $\mathrm{K}={\mathrm{c}}_{\mathrm{s}}/{\mathrm{c}}_{\mathrm{m}}$

Partition coefficient is larger :

The given equation is $\mathrm{K}={\mathrm{c}}_{\mathrm{s}}/{\mathrm{c}}_{\mathrm{m}}$

The concentration of the solute in the stationary phase is ${\mathrm{c}}_{\mathrm{s}}$proportional to the partition coefficient K

If a concentration in stationary phase increases there is more concentration that needs to be extracted to the mobile phase and the elution would be longer.