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44-525: (Redirected from WAX ) [REDACTED] Look up wax in Wiktionary, the free dictionary. Wax is a class of chemical compounds and mixtures, but may also refer to: People [ edit ] Wax (surname) Wax (rapper) , American rapper Wax (singer) , Korean singer Places [ edit ] Wax, Kentucky Wax Lake , Louisiana Music [ edit ] Wax (Indochine album) ,

88-505: A ketone / ˈ k iː t oʊ n / is an organic compound with the structure R−C(=O)−R' , where R and R' can be a variety of carbon -containing substituents . Ketones contain a carbonyl group −C(=O)− (a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl ), with the formula (CH 3 ) 2 CO . Many ketones are of great importance in biology and industry. Examples include many sugars ( ketoses ), many steroids (e.g., testosterone ), and

132-429: A values estimated to be somewhere between –5 and –7. Although acids encountered in organic chemistry are seldom strong enough to fully protonate ketones, the formation of equilibrium concentrations of protonated ketones is nevertheless an important step in the mechanisms of many common organic reactions, like the formation of an acetal, for example. Acids as weak as pyridinium cation (as found in pyridinium tosylate) with

176-461: A 1996 album Wax (KT Tunstall album) , a 2018 album Waxed , a 1995 album by Norwegian band Bigbang Wax (American band) , a California punk rock band Wax (British band) , a 1980s pop group featuring Andrew Gold and Graham Gouldman Wax Ltd , a production and songwriting team of Wally Gagel and Xandy Barry Other uses [ edit ] Wax or the Discovery of Television Among

220-440: A coating for many cheeses , and to waterproof leather and fabric. Wax has been used since antiquity as a temporary, removable model in lost-wax casting of gold , silver and other materials. Wax with colorful pigments added has been used as a medium in encaustic painting , and is used today in the manufacture of crayons , china markers and colored pencils . Carbon paper , used for making duplicate typewritten documents

264-431: A flash point >500 °F (>260 °C). Many polyethylene resin plants produce a low molecular weight stream often referred to as low polymer wax (LPW). LPW is unrefined and contains volatile oligomers, corrosive catalyst and may contain other foreign material and water. Refining of LPW to produce a polyethylene wax involves removal of oligomers and hazardous catalyst. Proper refining of LPW to produce polyethylene wax

308-424: A mixture of carboxylic acids having lesser number of carbon atoms than the parent ketone. Ketones do not appear in standard amino acids , nucleic acids, nor lipids. The formation of organic compounds in photosynthesis occurs via the ketone ribulose-1,5-bisphosphate . Many sugars are ketones, known collectively as ketoses . The best known ketose is fructose ; it mostly exists as a cyclic hemiketal , which masks

352-558: A p K a of 5.2 are able to serve as catalysts in this context, despite the highly unfavorable equilibrium constant for protonation ( K eq  < 10 ). An important set of reactions follow from the susceptibility of the carbonyl carbon toward nucleophilic addition and the tendency for the enolates to add to electrophiles. Nucleophilic additions include in approximate order of their generality: Ketones are cleaved by strong oxidizing agents and at elevated temperatures. Their oxidation involves carbon–carbon bond cleavage to afford

396-432: A significant fraction of petroleum. They are refined by vacuum distillation . Paraffin waxes are mixtures of saturated n- and iso- alkanes , naphthenes , and alkyl - and naphthene-substituted aromatic compounds. A typical alkane paraffin wax chemical composition comprises hydrocarbons with the general formula C n H 2 n +2 , such as hentriacontane , C 31 H 64 . The degree of branching has an important influence on

440-414: A variety of fatty acids and carboxylic alcohols. In waxes of plant origin, characteristic mixtures of unesterified hydrocarbons may predominate over esters. The composition depends not only on species, but also on geographic location of the organism. The best-known animal wax is beeswax , used in constructing the honeycombs of beehives, but other insects also secrete waxes. A major component of beeswax

484-450: Is methyl vinyl ketone , CH 3 C(O)CH=CH 2 , a α,β-unsaturated carbonyl compound . Many ketones are cyclic. The simplest class have the formula (CH 2 ) n CO , where n varies from 2 for cyclopropanone ( (CH 2 ) 2 CO ) to the tens. Larger derivatives exist. Cyclohexanone ( (CH 2 ) 5 CO ), a symmetrical cyclic ketone, is an important intermediate in the production of nylon . Isophorone , derived from acetone,

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528-671: Is polar because the electronegativity of the oxygen is greater than that for carbon. Thus, ketones are nucleophilic at oxygen and electrophilic at carbon. Because the carbonyl group interacts with water by hydrogen bonding , ketones are typically more soluble in water than the related methylene compounds. Ketones are hydrogen-bond acceptors. Ketones are not usually hydrogen-bond donors and cannot hydrogen-bond to themselves. Because of their inability to serve both as hydrogen-bond donors and acceptors, ketones tend not to "self-associate" and are more volatile than alcohols and carboxylic acids of comparable molecular weights . These factors relate to

572-924: Is a fossilized wax extracted from coal and lignite . It is very hard, reflecting the high concentration of saturated fatty acids and alcohols. Although dark brown and odorous, they can be purified and bleached to give commercially useful products. As of 1995 , about 200 million kilograms of polyethylene waxes were consumed annually. Polyethylene waxes are manufactured by one of three methods: Each production technique generates products with slightly different properties. Key properties of low molecular weight polyethylene waxes are viscosity, density and melt point. Polyethylene waxes produced by means of degradation or recovery from polyethylene resin streams contain very low molecular weight materials that must be removed to prevent volatilization and potential fire hazards during use. Polyethylene waxes manufactured by this method are usually stripped of low molecular weight fractions to yield

616-405: Is an unsaturated, asymmetrical ketone that is the precursor to other polymers . Muscone , 3-methylpentadecanone, is an animal pheromone . Another cyclic ketone is cyclobutanone , having the formula (CH 2 ) 3 CO . An aldehyde differs from a ketone in that it has a hydrogen atom attached to its carbonyl group, making aldehydes easier to oxidize. Ketones do not have a hydrogen atom bonded to

660-554: Is an unsymmetrical ketone. Many kinds of diketones are known, some with unusual properties. The simplest is diacetyl (CH 3 C(O)C(O)CH 3 ) , once used as butter-flavoring in popcorn . Acetylacetone (pentane-2,4-dione) is virtually a misnomer (inappropriate name) because this species exists mainly as the monoenol CH 3 C(O)CH=C(OH)CH 3 . Its enolate is a common ligand in coordination chemistry . Ketones containing alkene and alkyne units are often called unsaturated ketones. A widely used member of this class of compounds

704-455: Is especially important when being used in applications requiring FDA or other regulatory certification. Waxes are mainly consumed industrially as components of complex formulations, often for coatings. The main use of polyethylene and polypropylene waxes is in the formulation of colourants for plastics. Waxes confer matting effects (i.e., to confer non-glossy finishes) and wear resistance to paints. Polyethylene waxes are incorporated into inks in

748-859: Is frequently used as a lubricant on drawer slides where wood to wood contact occurs. Sealing wax was used to close important documents in the Middle Ages . Wax tablets were used as writing surfaces. There were different types of wax in the Middle Ages, namely four kinds of wax ( Ragusan , Montenegro , Byzantine , and Bulgarian ), "ordinary" waxes from Spain , Poland , and Riga , unrefined waxes and colored waxes (red, white, and green). Waxes are used to make waxed paper , impregnating and coating paper and card to waterproof it or make it resistant to staining, or to modify its surface properties. Waxes are also used in shoe polishes , wood polishes , and automotive polishes, as mold release agents in mold making , as

792-487: Is generally not useful for establishing the presence of a ketone, C NMR spectra exhibit signals somewhat downfield of 200 ppm depending on structure. Such signals are typically weak due to the absence of nuclear Overhauser effects . Since aldehydes resonate at similar chemical shifts , multiple resonance experiments are employed to definitively distinguish aldehydes and ketones. Ketones give positive results in Brady's test ,

836-425: Is myricyl palmitate which is an ester of triacontanol and palmitic acid . Its melting point is 62–65 °C (144–149 °F). Spermaceti occurs in large amounts in the head oil of the sperm whale . One of its main constituents is cetyl palmitate , another ester of a fatty acid and a fatty alcohol . Lanolin is a wax obtained from wool, consisting of esters of sterols . Plants secrete waxes into and on

880-631: The solvent acetone . The word ketone is derived from Aketon , an old German word for acetone . According to the rules of IUPAC nomenclature , ketone names are derived by changing the suffix -ane of the parent alkane to -anone . Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone . These nonsystematic names are considered retained IUPAC names, although some introductory chemistry textbooks use systematic names such as "2-propanone" or "propan-2-one" for

924-515: The Bees , a 1991 film Wax (Ethel Lina White novel) , a 1935 mystery Wax (cannabis) , a product extracted from cannabis See also [ edit ] Debugmode Wax , a video editor Hair wax , a type of hairstyling product Wax argument , thought experiment Wax gourd , a large Asian fruit WAXX , an American radio station Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

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968-522: The Brazilian palm Copernicia prunifera . Containing the ester myricyl cerotate, it has many applications, such as confectionery and other food coatings, car and furniture polish, floss coating, and surfboard wax . Other more specialized vegetable waxes include jojoba oil , candelilla wax and ouricury wax . Plant and animal based waxes or oils can undergo selective chemical modifications to produce waxes with more desirable properties than are available in

1012-517: The above reaction) include potassium permanganate or a Cr(VI) compound. Milder conditions make use of the Dess–Martin periodinane or the Moffatt–Swern methods. Many other methods have been developed, examples include: Ketones that have at least one alpha-hydrogen , undergo keto-enol tautomerization ; the tautomer is an enol . Tautomerization is catalyzed by both acids and bases. Usually,

1056-628: The blood ( ketosis ) after fasting, including a night of sleep; in both blood and urine in starvation ; in hypoglycemia , due to causes other than hyperinsulinism ; in various inborn errors of metabolism , and intentionally induced via a ketogenic diet , and in ketoacidosis (usually due to diabetes mellitus). Although ketoacidosis is characteristic of decompensated or untreated type 1 diabetes , ketosis or even ketoacidosis can occur in type 2 diabetes in some circumstances as well. Ketones are produced on massive scales in industry as solvents, polymer precursors, and pharmaceuticals. In terms of scale,

1100-430: The carbonyl group, and are therefore more resistant to oxidation. They are oxidized only by powerful oxidizing agents which have the ability to cleave carbon–carbon bonds. Ketones (and aldehydes) absorb strongly in the infra-red spectrum near 1750 cm , which is assigned to ν C=O ("carbonyl stretching frequency"). The energy of the peak is lower for aryl and unsaturated ketones. Whereas H NMR spectroscopy

1144-493: The form of dispersions to decrease friction. They are employed as release agents , find use as slip agents in furniture, and confer corrosion resistance. Waxes such as paraffin wax or beeswax , and hard fats such as tallow are used to make candles , used for lighting and decoration. Another fuel type used in candle manufacturing includes soy . Soy wax is made by the hydrogenation process using soybean oil. Waxes are used as finishes and coatings for wood products. Beeswax

1188-455: The keto form is more stable than the enol. This equilibrium allows ketones to be prepared via the hydration of alkynes . C−H bonds adjacent to the carbonyl in ketones are more acidic p K a  ≈ 20) than the C−H bonds in alkane (p K a  ≈ 50). This difference reflects resonance stabilization of the enolate ion that is formed upon deprotonation . The relative acidity of

1232-473: The ketone functional group. Fatty acid synthesis proceeds via ketones. Acetoacetate is an intermediate in the Krebs cycle which releases energy from sugars and carbohydrates. In medicine, acetone , acetoacetate, and beta-hydroxybutyrate are collectively called ketone bodies , generated from carbohydrates , fatty acids , and amino acids in most vertebrates , including humans. Ketone bodies are elevated in

1276-458: The ketonic carbon, with C–C–O and C–C–C bond angles of approximately 120°. Ketones differ from aldehydes in that the carbonyl group (C=O) is bonded to two carbons within a carbon skeleton . In aldehydes, the carbonyl is bonded to one carbon and one hydrogen and are located at the ends of carbon chains. Ketones are also distinct from other carbonyl-containing functional groups , such as carboxylic acids , esters and amides . The carbonyl group

1320-533: The less-substituted kinetic enolate is generated selectively, while conditions that allow for equilibration (higher temperature, base added to ketone, using weak or insoluble bases, e.g., CH 3 CH 2 ONa in CH 3 CH 2 OH , or NaH ) provides the more-substituted thermodynamic enolate . Ketones are also weak bases, undergoing protonation on the carbonyl oxygen in the presence of Brønsted acids . Ketonium ions (i.e., protonated ketones) are strong acids, with p K

1364-469: The most important ketones are acetone , methylethyl ketone , and cyclohexanone . They are also common in biochemistry, but less so than in organic chemistry in general. The combustion of hydrocarbons is an uncontrolled oxidation process that gives ketones as well as many other types of compounds. Although it is difficult to generalize on the toxicity of such a broad class of compounds, simple ketones are, in general, not highly toxic. This characteristic

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1408-400: The oxo group (=O) and used as prefix when the ketone does not have the highest priority. Other prefixes, however, are also used. For some common chemicals (mainly in biochemistry), keto refer to the ketone functional group . The ketone carbon is often described as sp hybridized , a description that includes both their electronic and molecular structure. Ketones are trigonal planar around

1452-589: The performance. Some waxes are considered food-safe and are used to coat wooden cutting boards and other items that come into contact with food. Beeswax or coloured synthetic wax is used to decorate Easter eggs in Romania, Ukraine, Poland, Lithuania and the Czech Republic. Paraffin wax is used in making chocolate covered sweets. Wax is also used in wax bullets , which are used as simulation aids, and for wax sculpturing . Ketones In organic chemistry ,

1496-429: The pervasiveness of ketones in perfumery and as solvents. Ketones are classified on the basis of their substituents. One broad classification subdivides ketones into symmetrical and unsymmetrical derivatives, depending on the equivalency of the two organic substituents attached to the carbonyl center. Acetone and benzophenone ( (C 6 H 5 ) 2 CO ) are symmetrical ketones. Acetophenone (C 6 H 5 C(O)CH 3 )

1540-615: The preparation of ketones in industrial scale and academic laboratories. Ketones are also produced in various ways by organisms; see the section on biochemistry below. In industry, the most important method probably involves oxidation of hydrocarbons , often with air. For example, a billion kilograms of cyclohexanone are produced annually by aerobic oxidation of cyclohexane . Acetone is prepared by air-oxidation of cumene . For specialized or small scale organic synthetic applications, ketones are often prepared by oxidation of secondary alcohols : Typical strong oxidants (source of "O" in

1584-404: The properties. Microcrystalline wax is a lesser produced petroleum based wax that contains higher percentage of isoparaffinic (branched) hydrocarbons and naphthenic hydrocarbons. Millions of tons of paraffin waxes are produced annually. They are used in foods (such as chewing gum and cheese wrapping), in candles and cosmetics, as non-stick and waterproofing coatings and in polishes. Montan wax

1628-433: The reaction with 2,4-dinitrophenylhydrazine to give the corresponding hydrazone. Ketones may be distinguished from aldehydes by giving a negative result with Tollens' reagent or with Fehling's solution . Methyl ketones give positive results for the iodoform test . Ketones also give positive results when treated with m -dinitrobenzene in presence of dilute sodium hydroxide to give violet coloration. Many methods exist for

1672-448: The rules of IUPAC nomenclature , the alkyl groups are written alphabetically, for example ethyl methyl ketone . When the two alkyl groups are the same, the prefix "di-" is added before the name of alkyl group. The positions of other groups are indicated by Greek letters , the α-carbon being the atom adjacent to carbonyl group. Although used infrequently, oxo is the IUPAC nomenclature for

1716-400: The simplest ketone ( C H 3 −C(= O )−CH 3 ) instead of "acetone". The derived names of ketones are obtained by writing separately the names of the two alkyl groups attached to the carbonyl group, followed by "ketone" as a separate word. Traditionally the names of the alkyl groups were written in order of increasing complexity, for example methyl ethyl ketone . However, according to

1760-408: The surface of their cuticles as a way to control evaporation, wettability and hydration. The epicuticular waxes of plants are mixtures of substituted long-chain aliphatic hydrocarbons, containing alkanes, alkyl esters, fatty acids, primary and secondary alcohols, diols , ketones and aldehydes. From the commercial perspective, the most important plant wax is carnauba wax , a hard wax obtained from

1804-1054: The title Wax . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Wax_(disambiguation)&oldid=1215897931 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages wax Waxes are organic compounds that characteristically consist of long aliphatic alkyl chains, although aromatic compounds may also be present. Natural waxes may contain unsaturated bonds and include various functional groups such as fatty acids , primary and secondary alcohols , ketones , aldehydes and fatty acid esters . Synthetic waxes often consist of homologous series of long-chain aliphatic hydrocarbons ( alkanes or paraffins) that lack functional groups . Waxes are synthesized by many plants and animals. Those of animal origin typically consist of wax esters derived from

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1848-410: The unmodified starting material. This approach has relied on green chemistry approaches including olefin metathesis and enzymatic reactions and can be used to produce waxes from inexpensive starting materials like vegetable oils. Although many natural waxes contain esters, paraffin waxes are hydrocarbons, mixtures of alkanes usually in a homologous series of chain lengths. These materials represent

1892-501: The α-hydrogen is important in the enolization reactions of ketones and other carbonyl compounds. The acidity of the α-hydrogen also allows ketones and other carbonyl compounds to react as nucleophiles at that position, with either stoichiometric and catalytic base. Using very strong bases like lithium diisopropylamide (LDA, p K a of conjugate acid ~36) under non-equilibrating conditions (–78 °C, 1.1 equiv LDA in THF, ketone added to base),

1936-440: Was coated with carbon black suspended in wax, typically montan wax , but has largely been superseded by photocopiers and computer printers . In another context, lipstick and mascara are blends of various fats and waxes colored with pigments, and both beeswax and lanolin are used in other cosmetics . Ski wax is used in skiing and snowboarding . Also, the sports of surfing and skateboarding often use wax to enhance

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