At what temperature does frozen pure water at sea level turn instantly to steam?

BRY2K

I believe the process you are referring to is called "sublimation". Sublimation of an element or compound is a transition from the solid to gas phase with no intermediate liquid stage. Per the specific variables that you have listed I cannot resource a precise temperature for this conversion from frozen pure H20 to instant steam. Having said that, here is what I learned about the process: "A lot more energy than is needed to convert water to ice (the latent heat of fusion), which is 80 calories/gram. And, it is also about five times the energy needed for heating water from the freezing point to the boiling point. In summary, energy is needed for the sublimation of ice to vapor to occur, and most of the energy is needed in the vaporiazation phase. A cubic centimeter (1 gram) of water in ice form requires 80 calories to melt, 100 calories to rise to boiling point, and another 540 calories to vaporize, a total of 720 calories. Sublimation requires the same energy input, but bypasses the liquid phase". http://ga.water.usgs.gov/edu/watercyclesublimation.html http://en.wikipedia.org/wiki/Sublimation_(chemistry) Jul 06 08, 4:30 AM