It is not possible for hot water to freeze faster than cold water in and of itself. This is simple thermo. While there are conditions where hot water will freeze faster, this is not due to the temperature alone, but the state -- the conditions in the experiment are no longer equivalent with temperature being the only difference.
All things being truly equal -- droplet particle size, gas content etc., cold will freeze faster. What happens in some of the winter videos is the near boiling water is already near an evaporative state. It is taken out into the very low humidity air and whipped into the air where some of it evaporates (cooling it quickly), and the rest is very small particles so it freezes very quickly.
That said, all things are not equal with temp being the only difference. If you built a machine to push cold mist into the same air, it would freeze faster than the hot mist of the same particle size. It's a gimmick of conditions rather than some twist of physics.
Evaporation plays two roles in these cases. One, it cools the remaining liquid, and two it leaves less liquid to freeze, so in essence not as much of the hot had to freeze -- again invalidating the experiment. This is why true experiments like this require a closed system.
That said, there may be cases where you can leverage the phenomenon effectively regardless of whether it is a "fair" assessment of what is happening.
All things being truly equal -- droplet particle size, gas content etc., cold will freeze faster. What happens in some of the winter videos is the near boiling water is already near an evaporative state. It is taken out into the very low humidity air and whipped into the air where some of it evaporates (cooling it quickly), and the rest is very small particles so it freezes very quickly.
That said, all things are not equal with temp being the only difference. If you built a machine to push cold mist into the same air, it would freeze faster than the hot mist of the same particle size. It's a gimmick of conditions rather than some twist of physics.
Evaporation plays two roles in these cases. One, it cools the remaining liquid, and two it leaves less liquid to freeze, so in essence not as much of the hot had to freeze -- again invalidating the experiment. This is why true experiments like this require a closed system.
That said, there may be cases where you can leverage the phenomenon effectively regardless of whether it is a "fair" assessment of what is happening.
