Liquid Boils and Freezes at the Same Time According to the description, these guys were “Evacuating a sample of unknown fluid (to vaporize for mass spectrometry). Pressure drop causes a decrease in temperature.” And they ended up finding the triple point of the substance where it exists as a solid, gas, and liquid at the same time. That means boiling and freezing. At the same time. Damn you and your seductive ways, Science.