[goanna_s]

Can someone tell me why, when analysing a mixture of water and ethanol, the water peak comes out first?

I thought that less polar, more volatile compunds would elute first....


Anna

[Vitnir]

If its a standard non-polar column then water doesnt interact with the solid phase very well, ethanol can interact and is chromatographed slower. If you had a MS-detector you would see traces of water during the entire run and ruins some of the resolution, a polar column would be a better choice.