I'm doing a science fair project on chromatography and I need some background info. What is chromatography?
Useful Science Fair demonstrations are where you demonstrate the separation of colours using paper chromatography. There is a nice forensic type demonstration I do with students. Source a number of different makes of water based black pens (I use white board marker pens and non-permanent Overhead Transparency pens). Write a note from the 'criminal' as a single line with one of the pens on paper. Cut the note into small squares. To transfer the ink to the chromatography paper (I use large filter papers) moisten the sample and press it onto the chromatogrpahy paper ink side down near the bottom of the paper. Then put a line of dots one from each pen next to the sample. Run the sample with water as the solvent like in
http://www.gcsescience.com/e8-chromatography.htm
The pattern from the pen that closely matches the criminals was the one that wrote the note.
The posts by UNKNOWN have been removed because they have been plagiarized from various websites, including some of these:
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Thanks I'm sure my project will be a hit!
Chromatography is a laboratory technique used to separate and analyze the components of a mixture. It is based on the differential affinity of the components in the mixture for a mobile phase (liquid or gas) and a stationary phase (solid or liquid). The technique takes advantage of the fact that different molecules have different solubilities and interact differently with the stationary phase.
To understand chromatography better, you can follow these steps:
1. Start with a mixture: Chromatography is commonly used to separate mixtures of colored compounds, but it can also be applied to separate other types of substances.
2. Choose your stationary and mobile phases: The stationary phase can be a solid material packed into a column or a thin layer of material coated on a plate or paper. The mobile phase can be a liquid (liquid chromatography) or gas (gas chromatography).
3. Apply the mixture: You apply the mixture to the stationary phase, either as a solution that flows through a column or as spots on a plate or paper.
4. Develop or elute: The mobile phase, either a liquid or gas, is passed through the stationary phase. As it moves, different components of the mixture interact differently with the stationary phase and the mobile phase, resulting in separation.
5. Detection and analysis: Once the components have separated, they can be detected. In chromatography, the separation is usually visualized as colored bands or spots. These can be further analyzed using various techniques, such as UV-Vis spectroscopy or mass spectrometry, to identify and quantify the components.
It's important to note that there are different types of chromatography techniques, such as thin-layer chromatography (TLC), gas chromatography (GC), liquid chromatography (LC), and high-performance liquid chromatography (HPLC). Each technique has its own advantages and applications.
By following these steps and understanding the principles behind chromatography, you can analyze mixtures in a controlled manner for your science fair project.