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The phenomenon, when taken to mean "hot water freezes faster than cold", is difficult to reproduce or confirm because it is ill-defined. [4] Monwhea Jeng proposed a more precise wording: "There exists a set of initial parameters, and a pair of temperatures, such that given two bodies of water identical in these parameters, and differing only in initial uniform temperatures, the hot one will ...
Hard rime forms by rapid freezing of supercooled water under at least moderate wind conditions. The droplets freeze more or less individually, leaving air gaps. Clear ice forms by slow freezing of supercooled water. Clear ice is typically transparent and homogeneous. Its amorphous and dense structure makes it adhesive.
During the final stage of freezing, an ice drop develops a pointy tip, which is not observed for most other liquids, and arises because water expands as it freezes. [10] Once the liquid is completely frozen, the sharp tip of the drop attracts water vapor in the air, much like a sharp metal lightning rod attracts electrical charges. [10]
If ice crystals are already present in this environment, the liquid droplets will freeze onto these crystals and be effectively removed before they can grow large enough to fall out of the cloud. As a result, freezing drizzle develops in shallow low-level stratus-type clouds where air saturation occurs entirely below the layer in which ice ...
Most liquids freeze by crystallization, formation of crystalline solid from the uniform liquid. This is a first-order thermodynamic phase transition, which means that as long as solid and liquid coexist, the temperature of the whole system remains very nearly equal to the melting point due to the slow removal of heat when in contact with air, which is a poor heat conductor.
When water freezes, it increases in volume (about 9% for fresh water). [8] The effect of expansion during freezing can be dramatic, and ice expansion is a basic cause of freeze-thaw weathering of rock in nature and damage to building foundations and roadways from frost heaving. It is also a common cause of the flooding of houses when water ...
Liquid droplets of rain that become supercooled while falling through a sub-freezing air mass and then freeze upon impact with any surface they encounter; the resulting glaze ice can accumulate to a thickness of several centimeters. Unlike mixed rain and snow, ice pellets, and hail, freezing rain exists entirely as a liquid until it hits a surface.
These ice particles end up as the nuclei of larger ice crystals. This process only happens at temperatures between 0 °C (32 °F) and −40 °C (−40 °F). Below −40 °C (−40 °F), liquid water will spontaneously nucleate, and freeze. The surface tension of the water allows the droplet to stay liquid well below its normal freezing point.