Hygroscopy is the ability of a substance to attract water molecules from the surrounding environment through either absorption or adsorption. Water is a common Chemical substance that is essential for the survival of all known forms of Life. In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by See also Nature The natural environment, commonly referred to simply as the environment, is a terminology that is comprised of all living and Absorption, in Chemistry, is a physical or chemical Phenomenon or a process in which Atoms Molecules, or Ions enter some Adsorption is a process that occurs when a gas or liquid Solute accumulates on the surface of a solid or a liquid (adsorbent forming a film of molecules or atoms (the
Hygroscopic substances include honey, glycerin, ethanol, methanol, concentrated sulfuric acid, methamphetamine, iodine[1], and concentrated sodium hydroxide (lye). Honey is a sweet and Viscous fluid produced by Honey bees (and some other species and derived from the nectar of Flowers According to the Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a Chemical compound Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic Sodium hydroxide ( Na[[hydroxide OH]]) also known as Lye, caustic soda and (incorrectly according to IUPAC nomenclature Lye is a Corrosive alkaline substance commonly Sodium hydroxide (NaOH Calcium chloride is so hygroscopic that it eventually dissolves in the water it absorbs: this property is called deliquescence (see below). Calcium chloride (CaCl2 is an ionic compound of Calcium and Chlorine. Because of their affinity for atmospheric moisture, hygroscopic materials may need to be stored in sealed containers. An atmosphere (from Greek ατμός - atmos, " Vapor " + σφαίρα - sphaira, " Sphere " When added to foods or other materials for the express purpose of maintaining moisture content, such substances are known as humectants. Water content or moisture content is the quantity of Water contained in a material such as Soil (called soil moisture) rock, A humectant is a Hygroscopic substance. It is often a molecule with several Hydrophilic groups most often Hydroxyl groups but Amines
Materials and compounds exhibit different hygroscopic properties, and this difference can lead to detrimental effects, such as stress concentration in composite materials. Composite materials (or composites for short are engineered Materials made from two or more constituent materials with significantly different physical or chemical The amount a particular material or compound is affected by ambient moisture may be considered its coefficient of hygroscopic expansion (CHE) (also referred to as CME, coefficient of moisture expansion) or coefficient of hygroscopic contraction (CHC)—the difference between the two terms being a difference in sign convention and a difference in point of view as to whether the difference in moisture leads to contraction or expansion.
A common example where difference in this hygroscopic property can be seen is in a paperback book cover. Often, in a relatively moist environment, the book cover will curl away from the rest of the book. The unlaminated side of the cover absorbs more moisture than the laminated side and increases in area, causing a stress that curls the cover toward the laminated side. This is similar to the function of a bi-metallic strip. A bi-metallic strip is used to convert a temperature change into mechanical displacement Inexpensive gauge-type hygrometers frequently seen domestically make use of this principle.
The similar-sounding but unrelated word hydroscopic is sometimes used in error for hygroscopic. A hydroscope is an optical device used for making observations deep under water. The word hydroscope is used to mean any of several instruments related to Water.
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Biology
The seeds of some grasses have hygroscopic extensions that bend with changes in humidity, enabling them to disperse over the ground. An example is Needle-and-Thread, Hesperostipa comata. Hesperostipa comata, commonly known as needle-and-thread grass, is a species of grass native to North America especially the western third Each seed has an awn that twists several turns when the seed is released. Increased moisture causes it to untwist, and, upon drying, to twist again; the seed is drilled into the ground.
Deliquescence
Deliquescent materials are substances (mostly salts) that have a strong affinity for moisture and will absorb relatively large amounts of water from the atmosphere if exposed to it, forming a liquid solution. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants In Chemical physics and Physical chemistry, chemical affinity can be defined as electronic properties by which dissimilar Chemical species are capable of Water is a common Chemical substance that is essential for the survival of all known forms of Life. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of In Chemistry, a solution is a Homogeneous Mixture composed of two or more substances Deliquescent salts include calcium chloride, magnesium chloride, zinc chloride, Carnallite (KCl*MgCl2*6H2O,), and the strong base sodium hydroxide. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants Calcium chloride (CaCl2 is an ionic compound of Calcium and Chlorine. Magnesium chloride is the name for the Chemical compounds with the formulas MgCl2 and its various hydrates MgCl2(H2Ox Zinc chloride is the name of Chemical compound with the formula Zn[[chlorine Cl]]2 and its hydrates Carnallite is an Evaporite mineral a hydrated Potassium Magnesium Chloride with formula K[[magnesium Mg]] Cl 3·6( Sodium hydroxide ( Na[[hydroxide OH]]) also known as Lye, caustic soda and (incorrectly according to IUPAC nomenclature They are often used as desiccants. A Desiccant is a Hygroscopic substance that induces or sustains a state of dryness ( Desiccation) in its local vicinity in a moderately-well sealed container
See also
References
In Chemistry, hydrophobicity (from the combining form of water in Attic Greek hydro- and for fear phobos) refers to the physical property of Hydrophile, from the Greek (hydros "water" and φιλια (philia "friendship" refers to a physical property of a MoleculeDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic