Write the next sentence in the following story.

How to perform column chromatography
Read and understand the lab procedure.
The goal of column chromatography is to separate and collect the desired chemical components from a mixture. Separation will occur within a column containing a stationary adsorbent and a mobile eluent (solvent).

Available options:
[I] Dissolution is the procedure through which an atom is separated from the ions. The procedure takes place in a concentration above 6 mercury ions (c).;
[II] An impure sample is introduced to the column and eluted (or separated) by running eluent through the column. Separation will occur because your impure mixture is made up of different chemical components that will be unevenly adsorbed (attached) to the surface of the adsorbent.;
[III] A still solids the substances in a molecule, while a fixed solvent bonds the entities and molecules in the interactive laboratory. Note that the patient will need to concurrently perform the chemical validation test for a volunteer patient.;
[IV] To separate two cells containing a catalytic compound used in solvent, divide the compound according to order of the number of elements (the solvent) you will need. How each cell (your new equation) is divided by another will vary from quick reaction to a long chemical reaction.;. The answer should be
[II]