what is split in G.C Analysis.How do you select the split ratio?

Answer 1

You use a split injection if you are getting too much sample onto the column. If you set the split ratio to 10:1, 1 part of the injected sample goes onto the column and 9 parts goes out the vent. As far as how to select the right split ratio, you are on your own there. You have to experiment to find out what ratio works best for your application.

Answer 2

Try the following webpages to see if this satisfies you.

http://www.chromatography-online.org/topics/split/ratio.html
http://openchemist.net/chemistry/show.php?id=analytical&story=instr001
http://www.shsu.edu/~chemistry/primers/pdf/GC.pdf