A solvent (from the Latinsolvō, "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules, and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell.
When one substance is dissolved into another, a solution is formed.[3] This is opposed to the situation when the compounds are insoluble like sand in water. In a solution, all of the ingredients are uniformly distributed at a molecular level and no residue remains. A solvent-solute mixture consists of a single phase with all solute molecules occurring as solvates (solvent-solute complexes), as opposed to separate continuous phases as in suspensions, emulsions and other types of non-solution mixtures. The ability of one compound to be dissolved in another is known as solubility; if this occurs in all proportions, it is called miscible.
In addition to mixing, the substances in a solution interact with each other at the molecular level. When something is dissolved, molecules of the solvent arrange around molecules of the solute. Heat transfer is involved and entropy is increased making the solution more thermodynamically stable than the solute and solvent separately. This arrangement is mediated by the respective chemical properties of the solvent and solute, such as hydrogen bonding, dipole moment and polarizability.[4] Solvation does not cause a chemical reaction or chemical configuration changes in the solute. However, solvation resembles a coordination complex formation reaction, often with considerable energetics (heat of solvation and entropy of solvation) and is thus far from a neutral process.
When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent. The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.
Solvent classifications
Solvents can be broadly classified into two categories: polar and non-polar. A special case is elemental mercury, whose solutions are known as amalgams; also, other metal solutions exist which are liquid at room temperature.
Generally, the dielectric constant of the solvent provides a rough measure of a solvent's polarity. The strong polarity of water is indicated by its high dielectric constant of 88 (at 0 °C).[5] Solvents with a dielectric constant of less than 15 are generally considered to be nonpolar.[6]
The dielectric constant measures the solvent's tendency to partly cancel the field strength of the electric field of a charged particle immersed in it. This reduction is then compared to the field strength of the charged particle in a vacuum.[6] Heuristically, the dielectric constant of a solvent can be thought of as its ability to reduce the solute's effective internal charge. Generally, the dielectric constant of a solvent is an acceptable predictor of the solvent's ability to dissolve common ionic compounds, such as salts.
Other polarity scales
Dielectric constants are not the only measure of polarity. Because solvents are used by chemists to carry out chemical reactions or observe chemical and biological phenomena, more specific measures of polarity are required. Most of these measures are sensitive to chemical structure.
The Grunwald–Winstein mY scale measures polarity in terms of solvent influence on buildup of positive charge of a solute during a chemical reaction.
Kosower's Z scale measures polarity in terms of the influence of the solvent on UV-absorption maxima of a salt, usually pyridiniumiodide or the pyridinium zwitterion.[7]
Donor number and donor acceptor scale measures polarity in terms of how a solvent interacts with specific substances, like a strong Lewis acid or a strong Lewis base.[8]
The Hildebrand parameter is the square root of cohesive energy density. It can be used with nonpolar compounds, but cannot accommodate complex chemistry.
Reichardt's dye, a solvatochromic dye that changes color in response to polarity, gives a scale of ET(30) values. ET is the transition energy between the ground state and the lowest excited state in kcal/mol, and (30) identifies the dye. Another, roughly correlated scale (ET(33)) can be defined with Nile red.
The polarity, dipole moment, polarizability and hydrogen bonding of a solvent determines what type of compounds it is able to dissolve and with what other solvents or liquid compounds it is miscible. Generally, polar solvents dissolve polar compounds best and non-polar solvents dissolve non-polar compounds best; hence "like dissolves like". Strongly polar compounds like sugars (e.g. sucrose) or ionic compounds, like inorganicsalts (e.g. table salt) dissolve only in very polar solvents like water, while strongly non-polar compounds like oils or waxes dissolve only in very non-polar organic solvents like hexane. Similarly, water and hexane (or vinegar and vegetable oil) are not miscible with each other and will quickly separate into two layers even after being shaken well.
Polarity can be separated to different contributions. For example, the Kamlet-Taft parameters are dipolarity/polarizability (π*), hydrogen-bonding acidity (α) and hydrogen-bonding basicity (β). These can be calculated from the wavelength shifts of 3–6 different solvatochromic dyes in the solvent, usually including Reichardt's dye, nitroaniline and diethylnitroaniline. Another option, Hansen solubility parameters, separates the cohesive energy density into dispersion, polar, and hydrogen bonding contributions.
Polar protic and polar aprotic
Solvents with a dielectric constant (more accurately, relative static permittivity) greater than 15 (i.e. polar or polarizable) can be further divided into protic and aprotic. Protic solvents, such as water, solvate anions (negatively charged solutes) strongly via hydrogen bonding. Polar aprotic solvents, such as acetone or dichloromethane, tend to have large dipole moments (separation of partial positive and partial negative charges within the same molecule) and solvate positively charged species via their negative dipole.[9] In chemical reactions the use of polar protic solvents favors the SN1reaction mechanism, while polar aprotic solvents favor the SN2 reaction mechanism. These polar solvents are capable of forming hydrogen bonds with water to dissolve in water whereas non-polar solvents are not capable of strong hydrogen bonds.
Physical properties
Properties table of common solvents
The solvents are grouped into nonpolar, polar aprotic, and polar protic solvents, with each group ordered by increasing polarity. The properties of solvents which exceed those of water are bolded.
The Hansen solubility parameter (HSP) values[13][14] are based on dispersion bonds (δD), polar bonds (δP) and hydrogen bonds (δH). These contain information about the inter-molecular interactions with other solvents and also with polymers, pigments, nanoparticles, etc. This allows for rational formulations knowing, for example, that there is a good HSP match between a solvent and a polymer. Rational substitutions can also be made for "good" solvents (effective at dissolving the solute) that are "bad" (expensive or hazardous to health or the environment). The following table shows that the intuitions from "non-polar", "polar aprotic" and "polar protic" are put numerically – the "polar" molecules have higher levels of δP and the protic solvents have higher levels of δH. Because numerical values are used, comparisons can be made rationally by comparing numbers. For example, acetonitrile is much more polar than acetone but exhibits slightly less hydrogen bonding.
If, for environmental or other reasons, a solvent or solvent blend is required to replace another of equivalent solvency, the substitution can be made on the basis of the Hansen solubility parameters of each. The values for mixtures are taken as the weighted averages of the values for the neat solvents. This can be calculated by trial-and-error, a spreadsheet of values, or HSP software.[13][14] A 1:1 mixture of toluene and 1,4 dioxane has δD, δP and δH values of 17.8, 1.6 and 5.5, comparable to those of chloroform at 17.8, 3.1 and 5.7 respectively. Because of the health hazards associated with toluene itself, other mixtures of solvents may be found using a full HSP dataset.
The boiling point is an important property because it determines the speed of evaporation. Small amounts of low-boiling-point solvents like diethyl ether, dichloromethane, or acetone will evaporate in seconds at room temperature, while high-boiling-point solvents like water or dimethyl sulfoxide need higher temperatures, an air flow, or the application of vacuum for fast evaporation.
Low boilers: boiling point below 100 °C (boiling point of water)
Medium boilers: between 100 °C and 150 °C
High boilers: above 150 °C
Density
Most organic solvents have a lower density than water, which means they are lighter than and will form a layer on top of water. Important exceptions are most of the halogenated solvents like dichloromethane or chloroform will sink to the bottom of a container, leaving water as the top layer. This is crucial to remember when partitioning compounds between solvents and water in a separatory funnel during chemical syntheses.
Often, specific gravity is cited in place of density. Specific gravity is defined as the density of the solvent divided by the density of water at the same temperature. As such, specific gravity is a unitless value. It readily communicates whether a water-insoluble solvent will float (SG < 1.0) or sink (SG > 1.0) when mixed with water.
Multicomponent solvents appeared after World War II in the USSR, and continue to be used and produced in the post-Soviet states. These solvents may have one or more applications, but they are not universal preparations.
Most organic solvents are flammable or highly flammable, depending on their volatility. Exceptions are some chlorinated solvents like dichloromethane and chloroform. Mixtures of solvent vapors and air can explode. Solvent vapors are heavier than air; they will sink to the bottom and can travel large distances nearly undiluted. Solvent vapors can also be found in supposedly empty drums and cans, posing a flash fire hazard; hence empty containers of volatile solvents should be stored open and upside down.
In addition some solvents, such as methanol, can burn with a very hot flame which can be nearly invisible under some lighting conditions.[20][21] This can delay or prevent the timely recognition of a dangerous fire, until flames spread to other materials.
Explosive peroxide formation
Ethers like diethyl ether and tetrahydrofuran (THF) can form highly explosive organic peroxides upon exposure to oxygen and light. THF is normally more likely to form such peroxides than diethyl ether. One of the most susceptible solvents is diisopropyl ether, but all ethers are considered to be potential peroxide sources.
The heteroatom (oxygen) stabilizes the formation of a free radical which is formed by the abstraction of a hydrogen atom by another free radical.[clarification needed] The carbon-centered free radical thus formed is able to react with an oxygen molecule to form a peroxide compound. The process of peroxide formation is greatly accelerated by exposure to even low levels of light, but can proceed slowly even in dark conditions.
Unless a desiccant is used which can destroy the peroxides, they will concentrate during distillation, due to their higher boiling point. When sufficient peroxides have formed, they can form a crystalline, shock-sensitive solid precipitate at the mouth of a container or bottle. Minor mechanical disturbances, such as scraping the inside of a vessel or the dislodging of a deposit, merely twisting the cap may provide sufficient energy for the peroxide to explode or detonate. Peroxide formation is not a significant problem when fresh solvents are used up quickly; they are more of a problem in laboratories which may take years to finish a single bottle. Low-volume users should acquire only small amounts of peroxide-prone solvents, and dispose of old solvents on a regular periodic schedule.
To avoid explosive peroxide formation, ethers should be stored in an airtight container, away from light, because both light and air can encourage peroxide formation.[22]
Peroxides may be removed by washing with acidic iron(II) sulfate, filtering through alumina, or distilling from sodium/benzophenone. Alumina degrades the peroxides but some could remain intact in it, therefore it must be disposed of properly.[23] The advantage of using sodium/benzophenone is that moisture and oxygen are removed as well.[24]
General health hazards associated with solvent exposure include toxicity to the nervous system, reproductive damage, liver and kidney damage, respiratory impairment, cancer, hearing loss,[25][26] and dermatitis.[27]
Chronic solvent exposures are often caused by the inhalation of solvent vapors, or the ingestion of diluted solvents, repeated over the course of an extended period.
Chronic exposure to organic solvents in the work environment can produce a range of adverse neuropsychiatric effects. For example, occupational exposure to organic solvents has been associated with higher numbers of painters suffering from alcoholism.[32] Ethanol has a synergistic effect when taken in combination with many solvents; for instance, a combination of toluene/benzene and ethanol causes greater nausea/vomiting than either substance alone.
A major pathway of induced health effects arises from spills or leaks of solvents, especially chlorinated solvents, that reach the underlying soil. Since solvents readily migrate substantial distances, the creation of widespread soil contamination is not uncommon; this is particularly a health risk if aquifers are affected.[34]Vapor intrusion can occur from sites with extensive subsurface solvent contamination.[35]
Solvents are often refluxed with an appropriate desiccant prior to distillation to remove water. This may be performed prior to a chemical synthesis where water may interfere with the intended reaction
^Kosower, E.M. (1969) "An introduction to Physical Organic Chemistry" Wiley: New York, p. 293
^Gutmann V (1976). "Solvent effects on the reactivities of organometallic compounds". Coord. Chem. Rev. 18 (2): 225. doi:10.1016/S0010-8545(00)82045-7.
^Anderson JE, Magyarl MW, Siegl WO (1 July 1985). "Concerning the Luminosity of Methanol-Hydrocarbon Diffusion Flames". Combustion Science and Technology. 43 (3–4): 115–125. doi:10.1080/00102208508947000. ISSN0010-2202.
^Raitta C, Husman K, Tossavainen A (August 1976). "Lens changes in car painters exposed to a mixture of organic solvents". Albrecht von Graefes Archiv für Klinische und Experimentelle Ophthalmologie. Albrecht von Graefe's Archive for Clinical and Experimental Ophthalmology. 200 (2): 149–56. doi:10.1007/bf00414364. PMID1086605. S2CID31344706.
Batu RusaDesaNegara IndonesiaProvinsiKepulauan Bangka BelitungKabupatenBangkaKecamatanMerawangKode pos33172Kode Kemendagri19.01.03.2001 Luas... km²Jumlah penduduk... jiwaKepadatan... jiwa/km² Kelenteng Kwanti di Batu Rusa. Untuk desa di Sumatera Selatan, lihat Batu Rusa, Pagar Gunung, Lahat. Batu Rusa adalah desa yang berada di kecamatan Merawang, Kabupaten Bangka, Kepulauan Bangka Belitung, Indonesia. lbsKecamatan Merawang, Kabupaten Bangka, Kepulauan Bangka BelitungDesa Air Anyir Baluni…
Namphan (município)GeografiaPaís MyanmarState of Myanmar ShanDistrito Lashio District (en)FuncionamentoEstatuto entidade territorial artificial (d)editar - editar código-fonte - editar Wikidata Namphan é uma cidade e município do estado de Xã, no Mianmar (Birmânia).[1] Referências ↑ «Unidade Administrativa da Informação de Myanmar: Mapa do estado de Shan» (PDF). Themimu.info. Consultado em 29 de novembro de 2012. Arquivado do original (PDF) em 29 de março de 2012…
Antonio de Alcedo Información personalNacimiento 1735 o 14 de marzo de 1736 Quito (Virreinato del Perú, Imperio español) Fallecimiento 1812 o 21 de septiembre de 1812 La Coruña (España) Nacionalidad EspañolaFamiliaPadre Dionisio de Alcedo Herrera Información profesionalOcupación Geógrafo, historiador, biógrafo, lexicógrafo y militar Género EnciclopediaObras notables Diccionario geográfico histórico de América Catálogo de autores americanos[editar datos en Wikidata] Anto…
Кумано — термін, який має кілька значень. Ця сторінка значень містить посилання на статті про кожне з них.Якщо ви потрапили сюди за внутрішнім посиланням, будь ласка, поверніться та виправте його так, щоб воно вказувало безпосередньо на потрібну статтю.@ пошук посилань сам
This is a list of flags that are inscribed with English-language text. # Flag Dates used English text 10th Mountain Division 2001–present MOUNTAIN 101st Airborne Division 2001–present AIRBORNE 82nd Airborne Division 2001–present 1. AIRBORNE2. AA[abbreviation of All American] A Flag Dates used English text Annapolis Royal –present ANNAPOLIS ROYAL N.S. Anne Arundel County, Maryland 1997–1998 1. ANNE ARUNDEL COUNTY2. MARYLAND Antigua and Barbuda (Governor) 1967–81 EACH E…
Квіліндсхі Гартман Особисті дані Народження 14 листопада 2001(2001-11-14) (22 роки) Звейндрехтd, Південна Голландія, Нідерланди Зріст 183 см Громадянство Нідерланди Позиція крайній захисник[1] Інформація про клуб Поточний клуб «Феєнорд» Номер 5 Юнацькі клуби 2009–2010 201…
Jesuit priest (1801–1873) The ReverendPierre-Jean De SmetSJc. 1860-65, by Mathew BradyBorn(1801-01-30)30 January 1801Dendermonde, French First Republic (now Belgium)Died23 May 1873(1873-05-23) (aged 72)St. Louis, MissouriOther namesPieter-Jan De SmetEducationWhite Marsh Novitiate,present-day Bowie, MarylandChurchCatholicOrdained23 September 1827 (1827-09-23) Pierre-Jean De Smet, SJ (Dutch and French IPA: [də smɛt]; 30 January 1801 – 23 May 1873), also known…
NATO Maritime Interdiction Operational Training Centre— NMIOTC — Aufstellung 12. Juni 2003 Organisation NATO NATO Typ Schulungs- und Trainingszentrum Unterstellung ACT Sitz Chania, Griechenland Website https://nmiotc.nato.int/ Befehlshaber Kommandeur Griechenland Kommodore Panagiotis Papanikolaou stellv. Kommandeur Turkei Captain Aykut Karasu Stabschef Griechenland Captain Charalampos Thymis Das NATO Maritime Interdiction Operational Training Centre (NMIOTC) ist ein Schulungs- und Traini…
SD KintelanNama sebagaimana tercantum dalamSistem Registrasi Nasional Cagar Budaya Cagar budaya IndonesiaKategoriBangunanNo. RegnasCB.237 (Peraturan Menteri Kebudayaan dan Pariwisata Republik Indonesia No. PM.89/PW.007/MKP/2011)LokasikeberadaanJalan Brigjend Katamso No. 163, Kalurahan Keparakan, Kemantrén Mergangsan, Kota Yogyakarta, Provinsi Daerah Istimewa YogyakartaTanggal SK17 Oktober 2011PemilikSekolah Dasar Negeri Kintelan IPengelolaKementerian Pendidikan, Kebudayaan, Riset, dan Teknologi…
Rohrendorf bei Krems Wappen Österreichkarte Rohrendorf bei Krems (Österreich) Basisdaten Staat: Österreich Bundesland: Niederösterreich Politischer Bezirk: Krems (Land) Kfz-Kennzeichen: KR Fläche: 9,77 km² Koordinaten: 48° 25′ N, 15° 39′ O48.41666666666715.65194Koordinaten: 48° 25′ 0″ N, 15° 39′ 0″ O Höhe: 194 m ü. A. Einwohner: 2.100 (1. Jän. 2023) Bevölkerungsdichte: 215 Einw. pro km² Postleit…
Esta é uma lista dos distritos paulistanos ordenada por Índice de Desenvolvimento Humano incluída no Atlas do Trabalho de Desenvolvimento do Município de São Paulo 2007. O Índice de Desenvolvimento Humano (IDH) é uma medida comparativa de riqueza, alfabetização, educação, esperança de vida, natalidade e outros fatores para os diversos países do mundo. É uma maneira padronizada de avaliação e medida do bem-estar de uma população, especialmente bem-estar infantil. Os 96 distritos…
State mosque in Malaysia Penang State MosqueMasjid Negeri Pulau Pinang பினாங்கு மாநில மசூதிPenang State Mosque seen from Penang Hill in 2023ReligionAffiliationIslamBranch/traditionSunniOwnershipState Government of PenangLocationLocationGeorge Town, Penang, MalaysiaShown within George Town, PenangGeographic coordinates5°24′24″N 100°18′05″E / 5.40667°N 100.30139°E / 5.40667; 100.30139ArchitectureArchitect(s)Efren Brindez PazTy…
Buddhist temple in Bangkok, Thailand This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Wat Phichai Yat – news · newspapers · books · scholar · JSTOR (March 2021) (Learn how and when to remove this template message) Wat Phichai YatFaçade of the ordination hallReligionAffiliationBuddhismSectTheravādaStatusactiveL…
Chemical compound ClopamideClinical dataTrade namesBrinaldixAHFS/Drugs.comInternational Drug NamesATC codeC03BA03 (WHO) Identifiers IUPAC name 4-chloro-N-(2,6-dimethyl-1-piperidyl)-3-sulfamoyl-benzamide CAS Number636-54-4 YPubChem CID2804ChemSpider2702 YUNII17S83WON0IKEGGD02460 YChEMBLChEMBL1361347 NCompTox Dashboard (EPA)DTXSID1022847 ECHA InfoCard100.010.238 Chemical and physical dataFormulaC14H20ClN3O3SMolar mass345.84 g·mol−13D model (JSmol)Interactive i…
Igreja de Santa Maria da Graça Igreja da Graça (Santarém) Nomes alternativos Igreja de Santo Agostinho da Graça, Convento da Graça Estilo dominante Gótico Início da construção 1380 Fim da construção I quartel séc XV Proprietário inicial Ordem dos Eremitas de Santo Agostinho Função inicial Convento masculino Proprietário atual Estado Português Função atual Igreja Património Nacional Classificação Monumento Nacional Ano 1910 DGPC 70431 SIPA 6540 Geografia País Portugal…
American Wiccan priestess Selena FoxBorn (1949-10-20) October 20, 1949 (age 74)Arlington, VirginiaOccupation(s)Wiccan priestesspsychotherapistSpouseDennis Carpenter Selena Fox (born 20 October 1949 in Arlington, Virginia[1]) is a Wiccan priestess, interfaith minister, environmentalist, pagan elder, author, and lecturer in the fields of pagan studies, ecopsychology, and comparative religion. Fox is a trained counselor and psychotherapist,[citation needed] with a B.S. cum laud…
Part of the War of the Second Coalition The neutrality of this article is disputed. Relevant discussion may be found on the talk page. Please do not remove this message until conditions to do so are met. (August 2022) (Learn how and when to remove this template message) Battle of BergenPart of the War of the Second CoalitionDate19 September 1799LocationBergen, Batavian Republic52°40′12″N 4°42′00″E / 52.6700°N 4.7000°E / 52.6700; 4.7000Result Franco-Dutch victo…
United States historic placeDutchess Quarry Cave SiteU.S. National Register of Historic Places Looking into the quarry from across Route 17A, 2007Show map of New YorkShow map of the United StatesLocationTown of Goshen, NYNearest cityMiddletownCoordinates41°21′35″N 74°21′29″W / 41.35972°N 74.35806°W / 41.35972; -74.35806Area177 acres (71 ha)NRHP reference No.74001289; 97000512Added to NRHP1974; boundaries increased 1997 The Dutchess Quarry Cave Site i…
Die Liste der Museen im Bezirk Innsbruck-Land gibt einen Überblick über aktuelle und ehemalige Museen im Bezirk Innsbruck-Land in Tirol. Inhaltsverzeichnis 1 Aktuelle Museen 2 Ehemalige Museen 3 Weblinks 4 Einzelnachweise Aktuelle Museen Gemeinde Name Kurzbeschreibung gegründet/eröffnet Träger Standort Bild Link Absam Gemeindemuseum Absam Das Museum zeigt Objekte zu Geschichte und Wirtschaft sowie Sommer- und Wintersport 2010 Gemeinde Absam !547.2953405511.5008805 Gasthof Kirchenwirt [1] Ab…
Artikel ini sebatang kara, artinya tidak ada artikel lain yang memiliki pranala balik ke halaman ini.Bantulah menambah pranala ke artikel ini dari artikel yang berhubungan atau coba peralatan pencari pranala.Tag ini diberikan pada Januari 2023. SMPLB Kembar Karya ISekolah Menengah Pertama Luar Biasa Kembar Karya IInformasiJenisSwastaAlamatLokasiJl. Bunga Rampai Iii No.22 Perumnas Klender, Jakarta Timur, DKI Jakarta, IndonesiaSitus webLaman di Kementerian Pendidikan Nasional, Republik Indone…