two uses of gaseous form water
short answer
Answers
Answer:
WATER, PROPERTIES
D. Hillel, in Encyclopedia of Soils in the Environment, 2005
States of Water
In the vapor or gaseous state, water molecules are largely independent of one another and occur mostly as monomers signified as (H2O)1. Occasionally, colliding molecules may fuse to form dimers (H2O)2 or even trimers, (H2O)3, but such combinations are rare. However, in the solid state a rigidly structured lattice forms with a tetrahedral configuration (Figure 2) that can be schematically depicted as sheets of puckered hexagonal rings (Figure 3). As many as nine alternative ice forms can occur when water freezes, depending on prevailing temperature and pressure conditions. Figure 3 pertains to ice 1, the familiar form, which occurs and is stable at ordinary atmospheric pressure.
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Figure 3. The crystalline structure of ice. Reprinted from Environmental Soil Physics, Hillel D (ed.). Copyright (1998), with permission from Elsevier.
The orderly structure of ice does not totally disappear in the liquid state. The polarity and hydrogen bonds continue to bind water molecules together, though the structural forms that develop in the liquid state are much more flexible and transient than in the rigidly structured solid state. Hydrogen bonds in liquid water form an extensive three-dimensional network, the detailed features of which appear to be short-lived. According to the ‘flickering cluster’ model discovered by Frank and Wen and modified by Erland, the molecules of liquid water associate and dissociate repeatedly in transitory or flickering polymer groups, designated (H2O)n, having a quasicrystalline internal structure. These microcrystals, as it were, form and melt so rapidly on the scale of picoseconds and randomly that, on a macroscopic scale, water appears to behave as a homogeneous liquid (Figure 4).
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Figure 4. Schematic illustration of ‘flickering clusters,’ showing polymeric associations and monomeric molecules in liquid water. Reprinted from Environmental Soil Physics, Hillel D (ed.). Copyright (1998), with permission from Elsevier.
In transition from solid to liquid, and from liquid to gas, hydrogen bonds must be broken (while in freezing and condensation they are re-established). Hence relatively high temperatures and energies are required to achieve these transitions. To thaw 1 kg of ice, 3.35×105 J (80 cal g−1) must be supplied. Conversely, the same energy (the latent heat of fusion) is released in freezing. At the boiling point (100°C at atmospheric pressure), water passes from the liquid to the gaseous state and in so doing it absorbs 2.26 × 106 J kg−1 (540 cal g−1). This amount of heat is known as the latent heat of vaporization. Water can be vaporized at temperatures below 100°C, but such vaporization requires greater heat or lower atmospheric pressure. At 30°C, the latent heat is about 2.43×106 J kg−1 (580 cal g−1). Sublimation is the direct transition from the solid state to vapor, and the heat absorbed by it is equal to the sum of the latent heats of fusion and of vaporization.
Explanation:
Explanation:
1.) steam
2.) Used in chemistry labs.