Search results
Results From The WOW.Com Content Network
Solid carbon dioxide sublimes rapidly along the solid-gas boundary (sublimation point) below the triple point (e.g., at the temperature of −78.5 °C, at atmospheric pressure), whereas its melting into liquid CO 2 can occur along the solid-liquid boundary (melting point) at pressures and temperatures above the triple point (i.e., 5.1 atm, − ...
Dry ice is the solid form of carbon dioxide (CO 2), a molecule consisting of a single carbon atom bonded to two oxygen atoms. Dry ice is colorless, odorless, and non-flammable, and can lower the pH of a solution when dissolved in water , forming carbonic acid (H 2 CO 3 ).
Images of carbon dioxide (b) and caffeine (d) in the solid state at room temperature and atmosphere. The gaseous phase of the dry ice in image (b) is visible because the molecular solid is subliming. A molecular solid is a solid consisting of discrete molecules.
In thermodynamics, the enthalpy of sublimation, or heat of sublimation, is the heat required to sublimate (change from solid to gas) one mole of a substance at a given combination of temperature and pressure, usually standard temperature and pressure (STP). It is equal to the cohesive energy of the solid.
A typical phase diagram.The solid green line applies to most substances; the dashed green line gives the anomalous behavior of water. In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium. [1]
Liquid carbon dioxide is the liquid state of carbon dioxide (CO 2 ), which cannot occur under atmospheric pressure. It can only exist at a pressure above 5.1 atm (5.2 bar; 75 psi), under 31.1 °C (88.0 °F) (temperature of critical point ) and above −56.6 °C (−69.9 °F) (temperature of triple point ). [ 1 ]
Supercritical carbon dioxide (s CO 2 ) is a fluid state of carbon dioxide where it is held at or above its critical temperature and critical pressure . Carbon dioxide usually behaves as a gas in air at standard temperature and pressure (STP), or as a solid called dry ice when cooled and/or pressurised sufficiently.
Outgassing is a challenge to creating and maintaining clean high-vacuum environments.NASA and ESA maintain lists of materials with low-outgassing properties suitable for use in spacecraft, as outgassing products can condense onto optical elements, thermal radiators, or solar cells and obscure them.