Heavy water (at 100% D enrichment): D2O
IUPAC nameDeuterium oxide
Other namesWater d2
Heavy water
Dideuterium monoxide
Identifiers
CAS number[7789-20-0]
RTECS numberZC0230000
Properties
Molar mass20. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Registry of Toxic Effects of Chemical Substances ( RTECS) is a Database of Toxicity information compiled from the open scientific literature without reference A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 04 g/mol
Appearancetransparent, colorless liquid
Density1. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 1056 g/mL, liquid (20°C)
1. 0177 g/cm3, solid (at m. p)
Melting point

3. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 82 °C, 38. 88 °F (276. 97 °K)

Boiling point

101. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid 4 °C, 214. 56 °F (374. 55 °K)

Viscosity0. Viscosity is a measure of the resistance of a Fluid which is being deformed by either Shear stress or Extensional stress. 00125 Pa·s at 20 °C
Dipole moment1. Viscosity is a measure of the resistance of a Fluid which is being deformed by either Shear stress or Extensional stress. In physics there are two kinds of dipoles ( Hellènic: di(s- = two- and pòla = pivot hinge An electric dipole is a 87 D
Hazards
MSDSExternal MSDS
NFPA 704
0
0
0

Related compounds
Related solventsacetone; methanol
Related compoundswater vapor; ice
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Heavy water is water which contains a higher proportion than normal of the isotope deuterium, as deuterium oxide, D2O or ²H2O, or as deuterium protium oxide, HDO or ¹H²HO. The debye (symbol D) is a non- SI, CGS unit of electrical dipole moment. A material safety data sheet ( MSDS) is a form containing data regarding the properties of a particular substance Symbolism The four divisions are typically color-coded with blue indicating level of Health Hazard, red indicating A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and β-ketopropane) is a colorless mobile flammable Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a Chemical compound General properties of water vapor Evaporation/sublimation Whenever a water molecule leaves a surface it is said to have evaporated Ice is a Solid phase, usually crystalline, of a Non-metalic substance that is liquid or gas at Room temperature, such as Ammonia In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides Deuterium, also called heavy hydrogen, is a Stable isotope of Hydrogen with a Natural abundance in the Oceans of Earth [1] Its physical and chemical properties are somewhat similar to those of water, H2O. Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as Heavy water may contain as much as 100% D2O, and usually the term refers to water which is highly enriched in deuterium. The isotopic substitution with deuterium alters the bond energy of the hydrogen-oxygen bond in water, altering the physical, chemical, and especially biological properties of the pure or highly-enriched substance to a larger degree than is found in most isotope-substituted chemical compounds. In Chemistry, bond energy ( E) is a measure of Bond strength in a Chemical bond.

Heavy water should not be confused with hard water or with tritiated water. Hard water is the type of Water that has high Mineral content (in contrast with Soft water) Tritiated water is a form of water where the usual hydrogen atoms are replaced with Tritium.

## Other meanings

### Semiheavy water

Semiheavy water, HDO, exists whenever there is water with hydrogen-1 (or protium) and deuterium present in the mixture. A hydrogen atom is an atom of the chemical element Hydrogen. The electrically neutral This is because hydrogen atoms (hydrogen-1 and deuterium) are rapidly exchanged between water molecules. Water containing 50% H and 50% D in its hydrogen actually contains about 50% HDO and 25% each of H2O and D2O, in dynamic equilibrium. A dynamic equilibrium occurs when two opposing Processes proceed at the same rate Semiheavy water, HDO, occurs naturally in regular water at a proportion of about 1 molecule in 3,200 (each hydrogen has a probability of 1 in 6,400 of being D). Heavy water, D2O, by comparison, occurs naturally at a proportion of about 1 molecule in 41 million (i. e. , 1 in 6,4002). This makes semiheavy water actually far more prevalent than 'normal' heavy water.

### Heavy-oxygen water

A common type of heavy-oxygen water H218O is available commercially for use as a non-radioactive isotopic tracer (see doubly-labeled water for discussion), and qualifies as "heavy water" insofar as having a higher density than normal water (in this case, similar density to deuterium oxide). Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Doubly-labeled water is water in which both the Hydrogen and the Oxygen has been partly or completely replaced for tracking purposes (i At higher expense (due to the greater difficulty in separation of O-17, a less common heavy isotope of oxygen), water is available in which the oxygen is enriched to varying degrees with 17O. However, these types of heavy-isotope water are rarely referred to as "heavy water", as they do not contain the deuterium which gives D2O its characteristically different nuclear and biological properties. Heavy-oxygen waters with normal hydrogen, for example, would not be expected to show any toxicity whatsoever (see discussion of toxicity below).

## Physical properties (with comparison to light water)

PropertyD2O (Heavy water)H2O (Light water)
Freezing point (°C)3. 820. 0
Boiling point (°C)101. 4100. 0
Density (at 20°C, g/mL)1. The litre or liter (see spelling differences) is a unit of Volume. 10560. 9982
Temp. of maximum density (°C)11. 64. 0
Viscosity (at 20°C, mPa·s)1. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units 251. 005
Surface tension (at 25°C, μJ)7. 1937. 197
Heat of fusion (cal/mol)1,5151,436
Heat of vaporisation (cal/mol)10,86410,515
pH (at 25°C)7. This article is about the unit of energy For its use in Nutrition and Food labelling regulations, see the article on Food energy. The mole (symbol mol) is a unit of Amount of substance: it is an SI base unit, and almost the only unit to be used to measure this 41 (sometimes "pD")7. 00

No physical properties are listed for "pure" semi-heavy water, because it cannot be isolated in bulk quantities. In the liquid state, a few water molecules are always in an ionised state, which means the hydrogen atoms can exchange among different oxygen atoms. The self-ionization of water (also autoionization of water, and autodissociation of water) is the chemical reaction in which two water molecules react to produce a A sample of hypothetical "pure" semi-heavy water would rapidly transform into a dynamic mixture of 25% light water, 25% heavy water, and 50% semi-heavy water.

Physical properties obvious by inspection: Heavy water is 10. 6% more dense than ordinary water, a difference which is nearly impossible to notice in a sample of it (which otherwise looks and tastes exactly like normal water). One of the few ways to demonstrate heavy water's physically different properties without equipment, is to freeze a sample and drop it into normal water. Ice made from heavy water sinks in normal water. If the normal water is ice-cold this phenomenon may be observed long enough for a good demonstration, since heavy-water ice has a slightly higher melting-temperature (3. 8 °C) than normal ice, and thus holds up very well in ice-cold normal water. [2]

## History

Harold Urey discovered the isotope deuterium in 1931 and was later able to concentrate it in water. Harold Clayton Urey ( April 29, 1893 &ndash January 5, 1981) was an American Physical chemist whose pioneering work Deuterium, also called heavy hydrogen, is a Stable isotope of Hydrogen with a Natural abundance in the Oceans of Earth Year 1931 ( MCMXXXI) was a Common year starting on Thursday (link will display full 1931 calendar of the Gregorian calendar. [3] Urey's mentor Gilbert Newton Lewis isolated the first sample of pure heavy water by electrolysis in 1933. Gilbert Newton Lewis ( October 23, 1875 - March 23, 1946) was a famous American physical chemist known for the discovery In chemistry and manufacturing electrolysis is a method of separating chemically bonded elements and compounds by passing an Electric current Year 1933 ( MCMXXXIII) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar. George de Hevesy and Hoffer used heavy water in 1934 in one of the first biological tracer experiments, to estimate the rate of turnover of water in the human body. Georg Karl von Hevesy ( August 1, 1885 &ndash July 5, 1966) was a Hungarian radiochemist and Nobel laureate recognised The history of large-quantity production and use of heavy water in early nuclear experiments is given below. [4]

## Effect on biological systems

Heavy isotopes of chemical elements have very slightly different chemical behaviors, but for most elements the differences in chemical behavior between isotopes are far too small to use, or even detect. For hydrogen, however, this is not true. The larger chemical isotope-effects seen with deuterium and tritium manifest because bond energies in chemistry are determined in quantum mechanics by equations in which the quantity of reduced mass of the nucleus and electrons appears. Tritium (ˈtɹɪtiəm symbol or, also known as Hydrogen-3) is a radioactive Isotope of Hydrogen. Reduced mass is the "effective" Inertial mass appearing in the Two-body problem of Newtonian mechanics. This quantity is altered in heavy-hydrogen compounds (of which deuterium oxide is the most common and familiar) far more than for heavy-isotope substitution in other chemical elements. This isotope effect of heavy hydrogen is magnified further in biological systems, which are very sensitive to small changes in the solvent properties of water.

Heavy water is the only known chemical substance which affects the period of circadian oscillations, consistently increasing them. The effect is seen in unicellular organisms, green plants, isopods, insects, birds, mice, and hamsters. The mechanism is unknown. [5]

To perform their tasks, enzymes rely on their finely tuned networks of hydrogen bonds, both in the active center with their substrates, and outside the active center, to stabilize their tertiary structures. Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen In Biochemistry and Chemistry, the tertiary structure of a Protein or any other Macromolecule is its three-dimensional structure as defined As a hydrogen bond with deuterium is slightly stronger than one involving ordinary hydrogen, in a highly deuterated environment, some normal reactions in cells are disrupted.

Particularly hard-hit by heavy water are the delicate assemblies of mitotic spindle formation necessary for cell division in eukaryotes. In Cell biology, the spindle apparatus (also called spindle fibers) is the structure that separate the Chromosomes into the daughter cells during Mitosis is the process in which a Eukaryotic cell separates the Chromosomes in its Cell nucleus, into two identical sets in two daughter nuclei Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Plants stop growing and seeds do not germinate when given only heavy water, because heavy water stops eukaryotic cell division.

## Effect on animals

Experiments in mice, rats, and dogs[6] have shown that a degree of 25% deuteration causes (sometimes irreversible) sterility, because neither gametes nor zygotes can develop. A gamete (from Ancient Greek γαμέτης; translated gamete = wife gametes = husband is a cell that fuses with another gamete For other meanings see Zygote (disambiguation. A zygote (from Greek ζυγωτός zugōtos "joined" or "yoked" High concentrations of heavy water (90%) rapidly kills fish, tadpoles, flatworms, and drosophila. Fish are aquatic Vertebrate animals that are typically ectothermic (previously Cold-blooded) covered with scales, and equipped with two A tadpole or polliwog (also pollywog, polliwig, polewig, or polwig) is the wholly aquatic larval stage in the life cycle of The flatworms (Phylum Platyhelminthes from the Greek πλατύ platy, meaning "flat" and ἕλμινς (root ἑλμινθ- helminth- Drosophila is a Genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" Mammals such as rats given heavy water to drink die after a week, at a time when their body water approaches about 50% deuteration. Rats are various medium sized long-tailed Rodents of the superfamily Muroidea The mode of death appears to be the same as that in cytotoxic poisoning (such as chemotherapy) or in acute radiation syndrome (though deuterium is not radioactive), and is due to deuterium's action in generally inhibiting cell division. Cytotoxicity is the quality of being toxic to cells Examples of toxic agents are a Chemical substance, an Immune cell or some types of Venom Chemotherapy, in its most general sense refers to treatment of disease by chemicals that kill cells specifically those of micro-organisms or Cancer. Deuterium oxide is used to enhance boron neutron capture therapy. Boron neutron capture therapy (BNCT is an experimental form of Radiotherapy that utilizes a Neutron beam that interacts with Boron injected to a patient [6] It is more toxic to malignant cells than normal cells but the concentrations needed are too high for regular use. [6] As in chemotherapy, deuterium-poisoned mammals die of a failure of bone marrow (bleeding and infection) and intestinal-barrier functions (diarrhea and fluid loss). In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea

Notwithstanding the problems of plants and animals in living with too much deuterium, prokaryotic organisms such as bacteria (which do not have the mitotic problems induced by deuterium) may be grown and propagated in fully deuterated conditions, resulting in replacement of all hydrogen atoms in the bacterial proteins and DNA with the deuterium isotope. The prokaryotes (proʊˈkærioʊts singular prokaryote /proʊˈkæriət/ are a group of Organisms that lack a Cell nucleus (= karyon or any other [6] Full replacement with heavy atom isotopes can be accomplished in higher organisms with other non-radioactive heavy isotopes (such as carbon-13, nitrogen-15, and oxygen-18), but this cannot be done for the stable heavy isotope of hydrogen.

## Toxicity in humans

Because it would take a very large amount of heavy water to replace 25% to 50% of a human being's body water (which in turn is 70% of body weight) with heavy water, accidental or intentional poisoning with heavy water is unlikely to the point of practical disregard. In the context of Biology, poisons are substances that can cause damage, Illness, or Death to Organisms usually by For a poisoning, large amounts of heavy water would need to be ingested without significant normal water intake for many days to produce any noticeable toxic effects (although in a few tests, volunteers drinking large amounts of heavy water have reported dizziness, a possible effect of density changes in the fluid in the inner ear). For example, a 70 kg human containing 50 kg of water and drinking 3 liters of pure heavy water per day, would need to do this for almost 5 days to reach 25% deuteration, and for about 11 days to approach 50% deuteration. Thus, it would take a week of drinking nothing but pure heavy water for a human to begin to feel ill, and 10 days to 2 weeks (depending on water intake) for severe poisoning and death. In the highly unlikely event that a human were to receive a toxic dose of heavy water, the treatment would involve the use of intravenous water replacement (due to possible intestinal dysfunction and problems with absorption of fluids). This would be done via 0. 9% (normal physiologic) saline solution with other salts as needed, perhaps in conjunction with diuretics. A diuretic is any Drug that elevates the rate of urination ( Diuresis)

Oral doses of heavy water in the multi-gram range, along with heavy oxygen 18O, are routinely used in human metabolic experiments. See doubly-labeled water testing. Doubly-labeled water is water in which both the Hydrogen and the Oxygen has been partly or completely replaced for tracking purposes (i Since 1 in every 6400 hydrogen atoms is deuterium, a 50 kg human containing 32 kg of body water would normally contain enough deuterium (about 1. 1 gram) to make 5. 5 grams of pure heavy water, so roughly this dose is required to double the amount of deuterium in the body.

## Production

On Earth, semiheavy water, HDO, occurs naturally in regular water at a proportion of about 1 molecule in 3200. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 This means that 1 in 6400 hydrogen atoms is deuterium, which is 1 part in 3200 by weight (hydrogen weight). The HDO may be separated from regular water by distillation or electrolysis and also by various chemical exchange processes, all of which exploit a kinetic isotope effect. Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture In chemistry and manufacturing electrolysis is a method of separating chemically bonded elements and compounds by passing an Electric current The kinetic isotope effect ( KIE) is a variation in the Reaction rate of a Chemical reaction when an Atom in one of the reactants is replaced (For more information about the isotopic distribution of deuterium in water, see Vienna Standard Mean Ocean Water. VSMOW, or Vienna Standard Mean Ocean Water, is an isotopic water standard defined in 1968 by the International Atomic Energy Agency. )

The difference in mass between the two hydrogen isotopes translates into a difference in the zero-point energy and thus into a slight difference in the speed at which the reaction proceeds. In Physics, the zero-point energy is the lowest possible Energy that a Quantum mechanical Physical system may possess and is the energy of the Once HDO becomes a significant fraction of the water, heavy water will become more prevalent as water molecules trade hydrogen atoms very frequently. To produce pure heavy water by distillation or electrolysis requires a large cascade of stills or electrolysis chambers, and consumes large amounts of power, so the chemical methods are generally preferred. The most important chemical method is the Girdler sulfide process. The Girdler sulfide (GS process, also known as the Geib-Spevack (GS process, is an industrial production method for making Heavy water ( deuterium oxide

### United States

In 1953, the United States began using heavy water in plutonium production reactors at the Savannah River Site. The United States of America —commonly referred to as the The Savannah River Site (SRS is a nuclear materials processing center in the United States state of South Carolina, located on land in Aiken Allendale and Barwnell The first of the five heavy water reactors came online in 1953, and the last was placed in cold shutdown in 1996. The SRS reactors were heavy water reactors so that they could produce both plutonium and tritium for the US nuclear weapons program. Tritium (ˈtɹɪtiəm symbol or, also known as Hydrogen-3) is a radioactive Isotope of Hydrogen.

The U. S. developed the Girdler Sulfide chemical exchange production process which was first demonstrated on a large scale at the Dana, Indiana plant in 1945 and at the Savannah River Plant, South Carolina in 1952. The Girdler sulfide (GS process, also known as the Geib-Spevack (GS process, is an industrial production method for making Heavy water ( deuterium oxide Dana is a town in Helt Township, Vermillion County, Indiana, United States. The SRP was operated by DuPont for the USDOE until April 1, 1989 at which time the operation was taken over by Westinghouse. E I du Pont de Nemours and Company (,) is an American chemical company that was founded in July 1802 as a Gunpowder mill by Eleuthère Irénée Events 527 - Byzantine Emperor Justin I names his nephew Justinian I as co-ruler and successor to the throne Year 1989 ( MCMLXXXIX) was a Common year starting on Sunday (link displays 1989 Gregorian calendar) For other uses see Westinghouse. The Westinghouse Electric Company (WEC is a multi-national nuclear technologies company a part of

### Norway

In 1934, Norsk Hydro built the first commercial heavy water plant at Vemork, Tinn, with a capacity of 12 tonnes per year. Norway ( Norwegian: Norge ( Bokmål) or Noreg ( Nynorsk) officially the Kingdom of Norway, is a Constitutional Year 1934 ( MCMXXXIV) was a Common year starting on Monday (link will display full 1934 calendar of the Gregorian calendar. Norsk Hydro ASA (,) is a Norwegian Aluminium and Renewable energy company headquartered in Oslo. Vemork is the name of an hydroelectric Power plant outside Rjukan in Tinn, Norway. Tinn is a municipality in the county of Telemark Norway. The parish of Tin was established as a municipality January 1 1838 (see Formannskapsdistrikt From 1940 and throughout World War II, the plant was under German control and the allies decided to destroy the plant and its heavy water to inhibit German development of nuclear weapons. Year 1940 ( MCMXL) was a Leap year starting on Monday (link will display the full 1940 calendar of the Gregorian calendar. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including Nazi Germany and the Third Reich are the common English names for Germany under the regime of Adolf Hitler and the National Socialist German Workers In late 1942, a raid by British paratroopers failed when the gliders they were in crashed. Year 1942 ( MCMXLII) was a Common year starting on Thursday (the link will display the full 1942 calendar of the Gregorian calendar. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located Paratroopers are Soldiers trained in Parachuting and generally operate as part of an airborne force. All the raiders were killed in the crash or shot by German army troops. But in the night of 27 February 1943 Operation Gunnerside succeeded. Events 1560 - The Treaty of Berwick, which would expel the French from Scotland, is signed by England and the Congregation Year 1943 ( MCMXLIII) was a Common year starting on Friday (the link will display full 1943 calendar of the Gregorian calendar. The Norwegian heavy water sabotage was a series of actions taken by Norwegian saboteurs during World War II to prevent the German nuclear energy project from acquiring Norwegian commandos managed to demolish small but key bits of the electrolytic cells, dumping the accumulated heavy water down the factory drains. Arguably (see below) this prevented Germany from building a nuclear reactor (German nuclear weapons would not have automatically followed the reactor for many reasons). The Norsk Hydro operation is one of the great commando/sabotage operations of the war.

On 16 November 1943, the allied air forces dropped more than 400 bombs on the site. Events 534 - A second and final revision of the Codex Justinianus is published Year 1943 ( MCMXLIII) was a Common year starting on Friday (the link will display full 1943 calendar of the Gregorian calendar. The allied air raid prompted the Nazi government to move all available heavy water to Germany for safekeeping. Nazism, which was a short name for National Socialism (Nationalsozialismus refers primarily to the Ideology and practices of the National Socialist German On 20 February 1944, a Norwegian partisan sank the ferry M/F Hydro carrying the heavy water across Lake Tinn, at the cost of 14 Norwegian civilians, and most of the heavy water was presumably lost. Events 1472 - Orkney and Shetland are left by Norway to Scotland, due to a Dowry payment Year 1944 ( MCMXLIV) was a Leap year starting on Saturday (link will display full calendar of the Gregorian calendar. Tinnsjå ( Tinnsjø, Tinnsjøen) is one of the largest lakes in Norway A few of the barrels were only half full, and therefore could float, and may have been salvaged and transported to Germany. (These events were dramatized in the 1965 movie, The Heroes of Telemark. The Heroes of Telemark is a 1965 War film directed by Anthony Mann based on the story of the Norwegian heavy water sabotage during )

However, recent investigation of production records at Norsk Hydro and analysis of an intact barrel that was salvaged in 2004 revealed that although the barrels in this shipment contained water of pH 14 — indicative of the alkaline electrolytic refinement process — they did not contain high concentrations of D2O. "MMIV" redirects here For the Modest Mouse album see " Baron von Bullshit Rides Again " pH is the measure of the acidity or alkalinity of a Solution. Despite the apparent size of shipment, the total quantity of pure heavy water was quite small, most barrels only containing between 1/2–1% pure heavy water. The Germans would have needed a total of about 5 tons of heavy water to get a nuclear reactor running. The manifest clearly indicated that there was only half a ton of heavy water being transported to Germany. The Hydro was carrying far too little heavy water for even one reactor, let alone the 10 or more tons needed to make enough plutonium for a nuclear weapon. The Hydro shipment on 20 February 1944 was probably destined for an experimental reactor project. Events 1472 - Orkney and Shetland are left by Norway to Scotland, due to a Dowry payment Year 1944 ( MCMXLIV) was a Leap year starting on Saturday (link will display full calendar of the Gregorian calendar.

As part of its contribution to the Manhattan Project, Canada built and operated a 6 tonnes per year electrolytic heavy water plant at Trail, BC, which started operation in 1943. Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb Trail is a city in the West Kootenay region of the Interior of British Columbia, Canada.

The Atomic Energy of Canada Limited (AECL) design of power reactor requires large quantities of heavy water to act as a neutron moderator and coolant. In Nuclear engineering, a neutron moderator is a medium which reduces the velocity of Fast neutrons thereby turning them into Thermal neutrons capable AECL ordered two heavy water plants which were built and operated in Atlantic Canada at Glace Bay (by Deuterium of Canada Limited) and Port Hawkesbury, Nova Scotia (by General Electric Canada). Atlantic Canada, also known as the Atlantic provinces, is the region of Canada comprising four provinces located on the Atlantic coast: Glace Bay (2001 pop 16984 is a community in the eastern part of the Cape Breton Regional Municipality. Port Hawkesbury ( 2006 population 3922 is a town located on the southwestern end of Cape Breton Island, on Nova Scotia (ˌnəʊvəˈskəʊʃə ( Latin for New Scotland; Alba Nuadh Nouvelle-Écosse is a Canadian province located on Canada 's These plants proved to have significant design, construction and production problems and so AECL built the Bruce Heavy Water Plant, which it later sold to Ontario Hydro, to ensure a reliable supply of heavy water for future power plants. Ontario Hydro was the official name from 1974 of the Hydro-Electric Power Commission of Ontario which was established in 1906 by the provincial Power Commission The two Nova Scotia plants were shut down in 1985 when their production proved to be unnecessary.

The Bruce Heavy Water Plant in Ontario was the world's largest heavy water production plant with a capacity of 700 tonnes per year. Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec It used the Girdler sulfide process to produce heavy water, and required 340,000 tonnes of feed water to produce one tonne of heavy water. The Girdler sulfide (GS process, also known as the Geib-Spevack (GS process, is an industrial production method for making Heavy water ( deuterium oxide It was part of a complex that included 8 CANDU reactors which provided heat and power for the heavy water plant. The CANDU reactor is a Canadian-invented Pressurized heavy water reactor developed initially in the late 1950s and 1960s by a partnership between Atomic Energy of The site was located at Douglas Point in Bruce County on Lake Huron where it had access to the waters of the Great Lakes. The Douglas Point Nuclear Generating Station was Canada’s first full-scale Nuclear power plant and the second CANDU Pressurised Heavy Water Reactor. Bruce County is a County in western Ontario, Canada, and includes the Bruce Peninsula. Lake Huron, bounded on the west by the US state of Michigan, and on the east by the province of Ontario, Canada, is one of the five Great The Laurentian Great Lakes are a chain of freshwater lakes located in eastern North America, on the Canada–United States border.

The Bruce plant was commissioned in 1979 to provide heavy water for a large increase in Ontario's nuclear power generation. Year 1979 ( MCMLXXIX) was a Common year starting on Monday (link displays the 1979 Gregorian calendar) The plants proved to be significantly more efficient than planned and only three of the planned four units were eventually commissioned. In addition, the nuclear power programme was slowed down and effectively stopped due to a perceived oversupply of electricity, later shown to be temporary, in 1993. Year 1993 ( MCMXCIII) was a Common year starting on Friday (link will display full 1993 Gregorian calendar) Improved efficiency in the use and recycling of heavy water plus the over-production at Bruce left Canada with enough heavy water for its anticipated future needs. Also, the Girdler process involves large amounts of hydrogen sulfide, raising environmental concerns if there should be a release. Hydrogen sulfide (or hydrogen sulphide) is the Chemical compound with the formula H 2 S. The Bruce heavy-water plant was shut down in 1997, after which the plant was gradually dismantled and the site cleared. Year 1997 ( MCMXCVII) was a Common year starting on Wednesday (link will display full 1997 Gregorian calendar

Atomic Energy of Canada Limited (AECL) is currently researching other more efficient and environmentally benign processes for creating heavy water. This is essential for the future of the CANDU reactors since heavy water represents about 20% of the capital cost of each reactor.

### India

India is the world's second largest producer of heavy water through its Heavy Water Board. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country

### Other countries

Argentina is another declared producer of heavy water, using an ammonia/hydrogen exchange based plant supplied by Switzerland's Sulzer company. For a topic outline on this subject see List of basic Argentina topics.

Romania also produces heavy water at the Drobeta Girdler Sulfide plant and has exported from time to time. Romania ( dated: Rumania, Roumania

United Kingdom The Department of Atomic Energy built a station at Loch Morar in 1947, possibly investigating using the loch as a source of heavy water. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located Loch Morar ( Scottish Gaelic: Loch Mhòrair) is a freshwater Loch in Morar, Lochaber, Highland, Scotland. [11]

## Applications

### Nuclear magnetic resonance

Deuterium oxide is used in nuclear magnetic resonance spectroscopy when the solvent of interest is water and the nuclide of interest is hydrogen. Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy, is the name given to a technique which exploits the magnetic properties of certain nuclei A nuclide (from lat nucleus is a species of Atom characterized by the constitution of its nucleus and hence by the number of Protons, the number of This is because the signal from the water solvent would interfere with the signal from the molecule of interest. Deuterium has a different magnetic moment from hydrogen and therefore does not contribute to the NMR signal at the hydrogen resonance frequency. In Physics, Astronomy, Chemistry, and Electrical engineering, the term magnetic moment of a system (such as a loop of Electric current Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1

### Neutron moderator

Because of this, heavy water reactors will be more efficient at breeding plutonium (from uranium-238) or uranium-233 (from thorium-232) than a comparable light-water reactor, leading them to be of greater concern in regards to nuclear proliferation. Heavy water reactors use Heavy water as a Neutron moderator. Heavy water is Deuterium Oxide, D2O Uranium-238 (U-238 is the most common isotope of Uranium found in nature Uranium-233 is a Fissile artificial isotope of Uranium, which has been used in a few Nuclear reactors and has been proposed for much wider use as a Thorium-232 is the primary abundant Nuclide of Thorium. It is a slightly unstable Radionuclide that is found in the earth's crust Nuclear proliferation is a term now used to describe the spread of Nuclear weapons, fissile material and weapons-applicable nuclear technology and information to nations The breeding and extraction of plutonium can be a relatively rapid and cheap route to building a nuclear weapon, as chemical separation of plutonium from fuel is easier than isotopic separation of U-235 from natural uranium. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. Isotope separation is the process of concentrating specific Isotopes of a Chemical element by removing other isotopes for example separating Natural uranium Heavy water moderated research reactors or specifically-built plutonium breeder reactors have been used for this purpose by most, if not all, states which possess nuclear weapons, although historically the first nuclear weapons were produced without it. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. (Pure carbon may be used as a moderator, even in unenriched uranium nuclear reactors. Thus, in the U. S. , the first experimental atomic reactor (1942), as well as the Manhattan Project Hanford production reactors which produced the plutonium for the Trinity test and Fat Man bombs, all used pure carbon neutron moderators and functioned with neither enriched uranium nor heavy water). The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb Trinity was the first test of technology for a Nuclear weapon. "Fat Man" is the codename for the Atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9

There is no evidence that civilian heavy water power reactors, such as the CANDU or Atucha designs, have been used for military production of fissile materials. The CANDU reactor is a Canadian-invented Pressurized heavy water reactor developed initially in the late 1950s and 1960s by a partnership between Atomic Energy of Atucha I is one of two operational Nuclear power plants of Argentina. In states which do not already possess nuclear weapons, the nuclear material at these facilities is under IAEA safeguards to discourage any such diversion. The International Atomic Energy Agency ( IAEA) is an international organization that seeks to promote the peaceful use of nuclear energy and to inhibit its

Due to its potential for use in nuclear weapons programs, the possession or import/export of large industrial quantities of heavy water are subject to government control in several countries. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. Suppliers of heavy water and heavy water production technology typically apply IAEA (International Atomic Energy Agency) administered safeguards and material accounting to heavy water. The International Atomic Energy Agency ( IAEA) is an international organization that seeks to promote the peaceful use of nuclear energy and to inhibit its (In Australia, the Nuclear Non-Proliferation (Safeguards) Act 1987. For a topic outline on this subject see List of basic Australia topics. ) In the U. S. and Canada, non-industrial quantities of heavy water (i. e. , in the gram to kg range) are routinely available through chemical supply dealers, and directly commercial companies such as the world's former major producer Ontario Hydro, without special license. Ontario Hydro was the official name from 1974 of the Hydro-Electric Power Commission of Ontario which was established in 1906 by the provincial Power Commission Current (2006) cost of a kilogram of 99. 98% reactor-purity heavy water, is about $600 to$700. Smaller quantities of reasonable purity (99. 9%) may be purchased from chemical supply houses at prices of roughly \$1 per gram.

### Metabolic rate testing in physiology/biology

Heavy water is employed as part of a mixture with H218O for a common and safe test of mean metabolic rate in humans and animals undergoing their normal activities. This metabolic test is usually called the doubly-labeled water test. Doubly-labeled water is water in which both the Hydrogen and the Oxygen has been partly or completely replaced for tracking purposes (i

### Space-based non-toxic cooling systems

Heavy water (D2O) has a similar high heat of fusion to regular water, but freezes at a slightly higher temperature. It has been proposed as a non-toxic heatsink for space based cooling applications, where D2O ice acts as a heatsink to remove water vapor in air, but without danger that the water vapor will freeze to water-ice, because D2O ice maintains temperatures too high for this to occur. See U.S. Patent 5,246,061 . Such a system has not yet been tested.

### Tritium production

Tritium is an important material in nuclear weapon design for boosted fission weapons and initiators, and also has civilian industrial applications. Tritium (ˈtɹɪtiəm symbol or, also known as Hydrogen-3) is a radioactive Isotope of Hydrogen. Nuclear weapon designs are physical chemical and engineering arrangements that cause the physics package of a nuclear weapon to detonate A boosted fission weapon usually refers to a type of Nuclear bomb that uses a small amount of fusion fuel to increase the rate and thus yield of a fission Some is created in heavy water moderated reactors when deuterium captures a neutron. Heavy water reactors use Heavy water as a Neutron moderator. Heavy water is Deuterium Oxide, D2O This reaction has a small cross-section and produces only small amounts of tritium, although enough so that cleaning tritium from the moderator may be desirable after several years to reduce the risk of tritium escape and radiation exposure. The total neutron cross section of an isotope of a Chemical element is the effective cross sectional area that an atom of that isotope presents to Neutron scattering

Production of large amounts of tritium in this way would require reactors with very high neutron fluxes, or with a very high proportion of heavy water to nuclear fuel and very low neutron absorption by other reactor material. Nuclear fuel is any material that can be consumed to derive Nuclear energy, by analogy to chemical Fuel that is burned to derive energy Neutron capture is a kind of Nuclear reaction in which an Atomic nucleus collides with one or more Neutrons and they merge to form a heavier nucleus The tritium would then have to be recovered by isotope separation from a much larger quantity of deuterium, unlike tritium production from lithium-6 (the present method of tritium production), where only chemical separation is needed. Isotope separation is the process of concentrating specific Isotopes of a Chemical element by removing other isotopes for example separating Natural uranium Naturally occurring Lithium ( Li) (standard atomic mass 6941(2 u) is composed of two stable Isotopes ( and, the latter being the more abundant

Deuterium's absorption cross section for thermal neutrons is . The neutron temperature, also called the neutron energy, indicates a free neutron's Kinetic energy, usually given in Electron volts The term 52 millibarns, while oxygen-16's is . A barn (symbol b) is a unit of Area. While the barn is not an SI unit it is accepted (although discouraged for use with the SI There are three stable isotopes of oxygen that lead to Oxygen ( O) having a standard atomic mass of 15 19 millibarns and oxygen-17's is . There are three stable isotopes of oxygen that lead to Oxygen ( O) having a standard atomic mass of 15 24 barn. 17O makes up . 038% of natural oxygen, which has an overall absorption cross section of . Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the 28 millibarns. Therefore in D2O with natural oxygen, 21% of neutron captures are on oxygen, a proportion that may rise further as 17O accumulates from neutron capture on 16O. Neutron capture is a kind of Nuclear reaction in which an Atomic nucleus collides with one or more Neutrons and they merge to form a heavier nucleus Also, 17O emits an alpha particle on capture, producing radioactive carbon-14. Alpha particles (named after and denoted by the first letter in the Greek alphabet, α consist of two Protons and two Neutrons bound together into a Carbon-14, 14C, or radiocarbon, is a Radioactive isotope of Carbon discovered on February 27, 1940, by

## References

1. ^ International Union of Pure and Applied Chemistry. The Norwegian heavy water sabotage was a series of actions taken by Norwegian saboteurs during World War II to prevent the German nuclear energy project from acquiring Cold fusion, sometimes called low energy nuclear reactions (LENR or condensed matter nuclear science, is a set of effects reported in controversial laboratory experiments VSMOW, or Vienna Standard Mean Ocean Water, is an isotopic water standard defined in 1968 by the International Atomic Energy Agency. Deuterium, also called heavy hydrogen, is a Stable isotope of Hydrogen with a Natural abundance in the Oceans of Earth The International Union of Pure and Applied Chemistry ( IUPAC) (aɪjuːpæk or ay-yoo-pec) is an international Non-governmental organization "heavy water". Compendium of Chemical Terminology Internet edition. Compendium of Chemical Terminology (ISBN 0-86542-684-8 is a book published by IUPAC containing internationally accepted definitions for terms in Chemistry.
2. ^ Gray, Theodore (2007). How 2.0. Popular Science. Retrieved on 2008-01-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1189 - Philip II of France and Richard I of England begin to assemble troops to wage the Third Crusade.
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