What are the two forms of chromatography?

• A. Planar and Column
• B. Paper and TLC
• C. HPLC and GLC
• D. Gas and Liquid

Answer: (A)

The main idea here is that chromatography is grouped by how the stationary phase is arranged. There are two broad forms: planar chromatography and column chromatography. In planar chromatography, the stationary phase is laid out on a flat surface, like a thin layer on a plate or on paper. The separation happens as the mobile phase moves across that surface, and you can see the spots or bands form on the plane. Examples include paper chromatography and thin-layer chromatography.

In column chromatography, the stationary phase is packed into a vertical column, and the mobile phase flows through it. Components separate along the length of the column based on how strongly they interact with the stationary phase. This form includes many common techniques such as HPLC and GC.

The other options mix specific techniques or refer to the mobile phase, not the overall form. So the two forms being tested are planar and column chromatography.