Quick centrifuge question for those of you experienced with benchwork that I have not been able to find addressed elsewhere. I'm doing a polar lipid analysis, the protocol says to use a biphasic mixture of hexane:methanol 1:1. I will then be centrifuging 5 mL of each within a 15 mL glass centrifuge tube 3000 rpm x 5 minutes. When centrifuging hexane, would it be appropriate to use a glass centrifuge tube that is capped or without a cap? I concerned about expansion from hexane but I am unsure if it would be good practice to use hexane in an uncapped centrifuge tube due to its volatility.