Chromotography

Chromotography

1. Chromotography is used to separate mixtures of coloured compounds

2. Mixtures suitable for chromotography include inks, dyes and colouring agents in food

3. Usually chromotography is carried out on paper.

4. How to do chromotography.

   • Step 1: A spot of mixture is placed near the bottom of a piece of paper
   • Step 2: The paper is then put upright into a suitable solvent like water.
   • Step 3: As the solvent soaks up the paper the mixture goes along with it.
   • Different components move at different speeds and this separates out the mixture

5. Rf values

   • Rf =distance moved by the compound / distance moved by the solvent
   • The Rf value of a particular compound is always the same