Why is partition chromatography classified as a liquid–liquid method?

Poins on partition chromatography as liquid liquid method:

• Partition chromatography operates as a liquid–liquid chromatographic method in which both the stationary and mobile phases exist in liquid form during separation. 
• The stationary phase remains immobilized as a thin liquid film while maintaining its liquid properties throughout the chromatographic process. 
• Separation occurs because solutes interact with two liquid environments rather than with a solid surface, distinguishing this method from adsorption-based chromatography.

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