Phase changes

Boiling is the rapid vaporization of a liquid, which typically occurs when a liquid is heated to a temperature such that its vapor pressure is above that of the surroundings, such as air pressure. Thus, a liquid may also boil when the pressure of the surrounding atmosphere is sufficiently reduced, such as the use of a vacuum pump or at high altitudes. Boiling occurs in three characteristic forms, which are nucleate, transition and film boiling. ...more on Wikipedia about "Boiling"

Boiling chips are small, irregularly shaped stones added to liquids to make them boil more smoothly. They provide nucleation sites so the liquid boils easily without becoming superheated. Without boiling chips, a liquid being heated in a smooth container can become superheated and "bump" in a sudden, sometimes violent release of vapor. ...more on Wikipedia about "Boiling chip"

Condensation is the change in phase of a substance to a denser phase, such as gas (or vapor) to a liquid. Condensation commonly occurs when a vapor is cooled to a liquid, but can also occur if a vapor is compressed (i.e., pressure on it increased) into a liquid, or undergoes a combination of cooling and compression. Liquid which has been condensed from a vapor is called condensate. A device or unit used to condense vapors into liquid is called a condenser. Condensers are typically coolers or heat exchangers which are used for various purposes, have various designs, and come in many sizes ranging from rather small (hand-held) to very large. ...more on Wikipedia about "Condensation"

In the renormalization group analysis of phase transitions in physics, a critical dimension is the dimensionality of space at which the character of the phase transition changes. Below the lower critical dimension there is no phase transition. Above the upper critical dimension the critical indices of the theory become the same as that in mean field theory. ...more on Wikipedia about "Critical dimension"

Critical Exponents are observed in second-order phase transitions. They characterize the power law behavior of many physical quantities as a function of ...more on Wikipedia about "Critical exponent"

Critical opalescence is a phenomenon in liquids close to their critical point, in which a normally transparent liquid appears milky due to density fluctuations at all possible wavelengths. ...more on Wikipedia about "Critical opalescence"

In physics, a critical point is the point of termination of a phase equilibrium curve, which separates two distinct phases. At this point, the phases are no longer distinguishable. ...more on Wikipedia about "Critical point (physics)"

Critical radius is the minimum size that must be formed by atoms clustering together in the liquid before the solid particle is stable and begins to grow. ...more on Wikipedia about "Critical radius"

The critical temperature, Tc, of a material is the temperature above which distinct liquid and gas phases do not exist. As the critical temperature is approached, the properties of the gas and liquid phases become the same. Above the critical temperature, there is only one phase. The critical pressure is the vapor pressure at the critical temperature. The critical molar volume is the volume of one mole of material at the critical temperature and pressure. On diagrams showing thermodynamic properties for a given substance, the point at critical temperature and critical pressure is called the critical point of the substance. ...more on Wikipedia about "Critical temperature"

Flash freezing refers to the application of supercooling in various kinds of industries whereby objects are quickly frozen by subjecting them to super low temperatures. ...more on Wikipedia about "Flash freezing"

In physics and chemistry, freezing is the process of cooling a liquid to the temperature (called freezing point) where it turns solid. Melting, the process of turning a solid to a liquid, is the opposite of freezing. Consequently the freezing point is the same temperature as the melting point. A pure substance has a fixed freezing point. ...more on Wikipedia about "Freezing"

Incongruent melting occurs when a substance does not melt uniformly and decomposes into another substance. For example, potassium feldspar (KAlSi3O8) decomposes to leucite (KAlSi2O6) when it melts. The decomposition is not complete, however. Most of the feldspar does melt, a portion of it decomposes to leucite and some quartz (SiO2) is left over, since the chemical formulas of potassium feldspar and leucite differ by SiO2. Another mineral that melts incongruently is enstatite (MgSiO3), which decomposes to forsterite (Mg2SiO4). Enstatite does melt congruently between pressures of 2.5 and 5.5 kilobars. ...more on Wikipedia about "Incongruent melting"

In chemistry, materials science, and physics, the liquidus is a line on a phase diagram above which a given substance is stable in the liquid phase. Most commonly, this line represents a transition temperature. The liquidus may be a straight line, or it may be curved, depending upon the substance. The liquidus is most often applied to binary systems such as solid solutions, including metal alloys. ...more on Wikipedia about "Liquidus"

In physics, melting is the process of heating a solid substance to a point (called the melting point) where it turns liquid. An object that has melted is molten. Freezing is the opposite of melting. It is the process of turning a liquid to a solid. Consequently the freezing point is the same temperature as the melting point. See the phase article for more detail. ...more on Wikipedia about "Melting" http://www.shortopedia.com moments.

Nucleation is the onset of a phase transition in a small but stable region. For example, bubbles of carbon dioxide nucleate shortly after the pressure is released from a container of carbonated liquid. Nucleation often occurs more easily at a pre-existing interface (heterogeneous nucleation), as happens on boiling chips and string used to make rock candy. Nucleation generally occurs with much more difficulty in the interior of a uniform substance, by a process called homogeneous nucleation. It is key to understanding the thermal processing of polymers, alloys, and some ceramics. It is also important in meteorology (see cloud seeding). ...more on Wikipedia about "Nucleation"

In physics, a phase transition, (or phase change) is the transformation of a thermodynamic system from one phase to another. The distinguishing characteristic of a phase transition is an abrupt sudden change in one or more physical properties, in particular the heat capacity, with a small change in a thermodynamic variable such as the temperature. Examples of phase transitions are: ...more on Wikipedia about "Phase transition"

A Pourbaix diagram, also known as a potential/pH diagram, maps out possible stable ( equilibrium) phases of an aqueous electrochemical system. Reactions are represented by boundary lines between phases. A Pourbaix diagram can be read much like a standard phase diagram with a different set of axes. ...more on Wikipedia about "Pourbaix diagram"

(Solidus) ---- In chemistry, materials science, and physics, the solidus is a line on a phase diagram below which a given substance is stable in the solid phase. Most commonly, this line represents a transition temperature. The solidus may be a straight line, or it may be curved, depending upon the substance. The solidus is most often applied to binary systems such as solid solutions, including metal alloys. ...more on Wikipedia about "Solidus"

Supercooling is the process of chilling a liquid below its freezing point, without it becoming solid. ...more on Wikipedia about "Supercooling"

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