Seperation

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What is chromatography?

Chromatography is a technique used for separating a mixture of chemical substances.

What is Paper chromatography?

Paper chromatography allows us to separate substances based on their solubilities

Stationary phase - Paper

Mobile phase - solvent (

Paper chromatography works because each chemical in the mixture will be attracted to the stationary phase (paper) to a different extent.

Chemicals that are strongly attracted to the stationary phase will not move very far.

Chemicals that are weakly attracted to the stationary phase will move up further up the paper.

A pure chemical will produce a single spot in all solvents

A mixture may separate into different spots depending on the solvent

Why do we draw our starting line in pencil?

If we drew the line in pen, the pen ink would move up the paper, with the solvent.