What will happen to fluid water of ambient temperature at atmospheric pressure if to pour out it in an outer space?
Space — very much, very cold place (here we wrote about where in the Universe there is самя a cold point with a temperature of substance of 0,5 K). On the strong cold as prompts us life experience, water turns into ice — crystallizes.
But space is also the close to ideal a vacuum which it is possible to reach. One atmosphere is equivalent to pressure 6 x 1022 atoms of Hydrogenium upon a square meter. In the best vacuum chambers on Earth scientists create pressure in billions of times smaller, but in interstellar space it falls to millions and billions of times are lower than terrestrial technical records.
And at underpressure water turns into gaseous state — boils.
So will occur if zhidkoy water appears at the same time at very low pressure and very low temperature — will freeze or will instantly boil, having turned into gas? The answer — in a water thermal capacity.
Space is cold, but even in intergalactic space water not bad keeps that heat which to it was once reported. To quench it up to the temperature, near absolute to zero, it is impossible — the difference between room (293 K) and average on space is too big. Besides at the moment when water appears in an airless cold gloom, surface tension forces will create water spheres, and the area of cooling will become minimum.
Thus process of cooling will go incredibly sluggishly — at least until each molecule does not appear in itself, in the distance from other corners of H2O.
And what will prevent molecules of water to rush in all directions? Pressure will become negligible, and transition to gaseous state can happen absolutely instantly! When molecules or groups of molecules of water appear relatively far apart in a gas cloud, they will instantly lose a kinetic energy, and their temperature will sharply fall. In what aggregate state water will appear then? To answer, we will look at the phase diagram of water. From it it is visible that if temperature falls to -50 °C, then any low pressure is already incapable to make it fluid or gaseous.
So, the sequence of events is as follows: getting to an outer space, water at first instantly becomes gaseous, and then freezes in the form of the tiny small pieces of ice filling interstellar emptiness.