The tonne ( / t ʌ n / or / t ɒ n / ; symbol: t ) is a unit of mass equal to 1,000 kilograms . It is a non-SI unit accepted for use with SI . It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the short ton ( United States customary units ) and the long ton ( British imperial units ). It is equivalent to approximately 2,204.6 pounds , 1.102 short tons, and 0.984 long tons. The official SI unit is the megagram ( Mg ), a less common way to express the same amount.
20-512: MCAA may refer to: Science Monochloroacetic acid Organizations Marine Corps Aviation Association , organization dedicated to the advancement of United States Marine Corps aviation Mason Contractors Association of America Minecraft Collegiate Athletics Association , the Minecraft equivalent to the NCAA Topics referred to by
40-493: A concentrated (at least 75%) solution of sulfuric acid . This method produces a highly pure product, unlike the halogenation route. However, the significant quantities of HCl released have led to the increased popularity of the halogenation route. Approximately 420,000 tonnes are produced globally per year. Most reactions take advantage of the high reactivity of the C−Cl bond. In its largest-scale application, chloroacetic acid
60-512: A large cask, or tun . A full tun, standing about a metre high, could easily weigh a tonne. See also the common German word de:Mülltonne (literal translation: garbage drum ). The spelling tonne pre-dates the introduction of the SI in 1960; it has been used with this meaning in France since 1842, when there were no metric prefixes for multiples of 10 and above, and is now used as the standard spelling for
80-586: A lesser extent to a long ton of 2,240 lb (1,016 kg), with the term tonne rarely used in speech or writing. Both terms are acceptable in Canadian English . Ton and tonne are both derived from a Germanic word in general use in the North Sea area since the Middle Ages (cf. Old English and Old Frisian tunne , Old High German and Medieval Latin tunna , German and French tonne ) to designate
100-535: Is a hazardous alkylating agent . The LD 50 for rats is 76 mg/kg. It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities. Tonnes The BIPM symbol for
120-550: Is converted to chloroacetyl chloride , a precursor to adrenaline (epinephrine). Displacement of chloride by sulfide gives thioglycolic acid , which is used as a stabilizer in PVC and a component in some cosmetics . Illustrative of its usefulness in organic chemistry is the O -alkylation of salicylaldehyde with chloroacetic acid, followed by decarboxylation of the resulting ether , producing benzofuran . Like other chloroacetic acids and related halocarbons , chloroacetic acid
140-480: Is different from Wikidata All article disambiguation pages All disambiguation pages Monochloroacetic acid Chloroacetic acid , industrially known as monochloroacetic acid ( MCA ), is the organochlorine compound with the formula Cl C H 2 C O 2 H . This carboxylic acid is a useful building block in organic synthesis . It is a colorless solid. Related compounds are dichloroacetic acid and trichloroacetic acid . Chloroacetic acid
160-438: Is little need to distinguish between metric and other tons, and the unit is spelled either as ton or tonne with the relevant prefix attached. A metric ton unit (mtu) can mean 10 kg (22 lb) within metal trading, particularly within the United States. It traditionally referred to a metric ton of ore containing 1% (i.e. 10 kg) of metal. The following excerpt from a mining geology textbook describes its usage in
180-419: Is prepared industrially by two routes. The predominant method involves chlorination of acetic acid , with acetic anhydride as a catalyst : This route suffers from the production of dichloroacetic acid and trichloroacetic acid as impurities, which are difficult to separate by distillation : The second method entails hydrolysis of trichloroethylene : The hydrolysis is conducted at 130–140 °C in
200-400: Is the joule . One tonne of TNT is approximately equivalent to 4.2 gigajoules. In the petroleum industry the tonne of oil equivalent (toe) is a unit of energy : the amount of energy released by burning one tonne of crude oil , approximately 42 GJ. There are several slightly different definitions. This is ten times as much as a tonne of TNT because atmospheric oxygen is used. Like
220-481: Is the mass of one cubic metre of pure water at 4 °C (39 °F). As a non-SI unit, the use of SI metric prefixes with the tonne does not fall within the SI standard. For multiples of the tonne, it is more usual to speak of thousands or millions of tonnes. Kilotonne, megatonne, and gigatonne are more usually used for the energy of nuclear explosions and other events in equivalent mass of TNT , often loosely as approximate figures. When used in this context, there
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#1732855694029240-466: Is used as a proxy for energy, usually of explosions (TNT is a common high explosive ). Prefixes are used: kiloton(ne), megaton(ne), gigaton(ne), especially for expressing nuclear weapon yield , based on a specific combustion energy of TNT of about 4.2 MJ / kg (or one thermochemical calorie per milligram ). Hence, 1 t TNT = approx. 4.2 GJ , 1 kt TNT = approx. 4.2 TJ , 1 Mt TNT = approx. 4.2 PJ . The SI unit of energy
260-448: Is used to prepare the thickening agent carboxymethyl cellulose and carboxymethyl starch . Chloroacetic acid is also used in the production of phenoxy herbicides by etherification with chlorophenols. In this way 2-methyl-4-chlorophenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid , and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) are produced. It is the precursor to the herbicide glyphosate and dimethoate . Chloroacetic acid
280-413: Is usually pronounced the same as ton ( / t ʌ n / ), but the final "e" can also be pronounced, i.e. " tunnie " ( / ˈ t ʌ n i / ). In Australia, the common and recommended pronunciation is / t ɒ n / . In the United States, metric ton is the name for this unit used and recommended by NIST; an unqualified mention of a ton typically refers to a short ton of 2,000 lb (907.2 kg) and to
300-424: The SI symbols for the tesla , megatesla, and millitesla, respectively, while Mt and mt are SI-compatible symbols for the megatonne (one teragram) and millitonne (one kilogram). If describing TNT equivalent units of energy, one megatonne of TNT is equivalent to approximately 4.184 petajoules . In English, tonne is an established spelling alternative to metric ton . In the United States and United Kingdom, tonne
320-513: The metric mass measurement in most English -speaking countries. In the United States, the unit was originally referred to using the French words millier or tonneau , but these terms are now obsolete. The British imperial and United States customary units are comparable to the tonne and the spelling of ton in English is the same, though they differ in mass. One tonne is equivalent to: A tonne
340-482: The particular case of tungsten: Tungsten concentrates are usually traded in metric tonne units (originally designating one tonne of ore containing 1% of WO 3 , today used to measure WO 3 quantities in 10 kg units. One metric tonne unit (mtu) of tungsten (VI) contains 7.93 kilograms of tungsten. In the case of uranium , MTU is sometimes used in the sense of metric ton of uranium (1,000 kg [2,200 lb]). The tonne of trinitrotoluene (TNT)
360-405: The same term [REDACTED] This disambiguation page lists articles associated with the title MCAA . 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=MCAA&oldid=1251963495 " Category : Disambiguation pages Hidden categories: Short description
380-505: The tonne is t, adopted at the same time as the unit in 1879. Its use is also official for the metric ton in the United States, having been adopted by the United States National Institute of Standards and Technology (NIST). It is a symbol, not an abbreviation, and should not be followed by a period . Use of lower case is significant, and use of other letter combinations can lead to ambiguity. For example, T, MT, mT, are
400-568: Was first prepared (in impure form) by the French chemist Félix LeBlanc (1813–1886) in 1843 by chlorinating acetic acid in the presence of sunlight, and in 1857 (in pure form) by the German chemist Reinhold Hoffmann (1831–1919) by refluxing glacial acetic acid in the presence of chlorine and sunlight , and then by the French chemist Charles Adolphe Wurtz by hydrolysis of chloroacetyl chloride ( ClCH 2 COCl ), also in 1857. Chloroacetic acid
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