Copyright © Philip M. Parker, INSEAD. Terms of Use.
Definition: Underwater |
UnderwaterAdjective1. Beneath the surface of the water; "submerged rocks". 2. (biology) growing or remaining under water; "viewing subaqueous fauna from a glass-bottomed boat"; "submerged leaves". Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
Date "underwater" was first used in popular English literature: sometime before 1651. (references) |
(From Wikipedia, the free Encyclopedia)
Timeline of underwater technology
- 1716 - Edmund Halley builds a diving bell
- 1772 - Sieur Freminet builds the first scuba device, but dies from lack of oxygen after 20 minutes
- 1801 - Robert Fulton builds the first submarine, the Nautilus
- 1819 - Augustus Siebe invents a diving suit which receives air pumped down from the surface
- 1934 - Charles Beebe dives to 3,028 feet using a bathysphere
- 1943 - Jacques-Yves Cousteau makes the first scuba dive with a compressed-air aqualung
- 1948 - Auguste Piccard sends the first bathyscape, FNRS-2, on unmanned dives
- 1954 - USS Nautilus, the first nuclear-powered submarine, is launched
- 1954 - first manned dives in FNRS-2
- 1956 - first wetsuit was introduced
- 1958 - USS Nautilus completes the first ever voyage under the polar ice to the North Pole and back
- 1960 - Jacques Piccard and Lieutenant Don Walsh, USN, descend to the deepest known point in the ocean in the bathyscape Trieste
- 1960 - USS Nautilus completes the first ever underwater circumnavigation
- 1983 - Orca Edge dive computer was introduced.
- 1985 - The wreck of the Titanic was found.
links
- other time lines (http://scuba.about.com/library/weekly/aa100198.htm )
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Timeline of underwater technology."
(From Wikipedia, the free Encyclopedia)
Below the surface of the water. U/W is shorthand for underwater
This article is a stub. You can help Wikipedia by fixing it.
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Underwater."
(From Wikipedia, the free Encyclopedia)
nah:Atl nds:Water simple:Water
Water is a chemical compound which is liquid at room temperature and standard pressure. It has the chemical formula H2O, meaning that one molecule of water is composed of 2 hydrogen atoms and one oxygen atom. Water is found almost everywhere on earth and is required by all known life. About 70% of the earth's surface is covered by water.
Properties
General
Name Water Chemical formula H2O Appearance Colourless liquid Physical
Formula weight 18.01528 amu Melting point 273 K (0 °C) Boiling point 373 K (100 °C) Critical temperature 674 K Critical Pressure 22.1x10^6?? Pa Density 1.0 ×103 kg/m3 Thermochemistry
ΔfH0gas -241.83 kJ/mol ΔfH0liquid -285.83 kJ/mol ΔfH0solid -291.83 kJ/mol S0gas, 1 bar 188.84 J/mol·K S0liquid, 1 bar 69.95 J/mol·K S0solid 41 J/mol·K Safety
Ingestion Necessary to life; excessive consumption can cause headache, confusion, and cramps, and can be fatal in athletes Inhalation Non-toxic. Can dissolve surfactant of lungs. Suffocation in water is called drowning. Skin Prolonged immersion may cause flaking (desquamation). Eyes Not dangerous. SI units were used where possible. Unless otherwise stated, standard conditions were used. Disclaimer and references
General
The solid state of water is known as (water) ice; the gaseous state is known as steam. The units of temperature (formerly the degree Celsius and now the Kelvin) are defined in terms of the triple point of water, 273.16 K (0.01 °C) and 611.2 Pa, the temperature and pressure at which solid, liquid, and gaseous water coexist in equilibrium.
At temperatures greater than 647 K and pressures greater than 22.064 MPa, a collection of water molecules assumes a supercritical condition, in which liquid-like clusters float within a vapor-like phase.
A body of water is a term for an ocean, sea, lake, river, stream, canal, pond, or the like. See water (resource) for information about fresh water supplies. See also beach, ferry, pier.
Chemists sometimes jokingly refer to water as dihydrogen monoxide or DHMO (see http://www.dhmo.org/),
the systematic covalent name of this molecule, especially in parodies of chemical research that call for this "lethal chemical" to be banned. The systematic acid name of water is hydroxic acid or hydroxilic acid, although these terms are rarely used.
The dipolar nature of water
An important feature of water is its polar nature. The water molecule forms an angle, with hydrogen atoms at the tips and oxygen at the vertex. Since oxygen has a higher electronegativity than hydrogen, the side of the molecule with the oxygen atom has a partial negative charge, relative to the hydrogen side. A molecule with such a charge difference is called a dipole. The charge differences cause water molecules to be attracted to each other (the relatively positive areas being attracted to the relatively negative areas) and to other polar molecules. This attraction is known as hydrogen bonding.
This relatively weak (relative to the covalent bonds within the water molecule itself) attraction results in properties such as a very high boiling point, because a lot of heat energy is necessary to break the hydrogen bonds between molecules, and also a large specific heat capacity.
Also due to hydrogen bonding, water molecules have the peculiar property that their density in the liquid state is higher than in the crystalline (solid) state. The highest density of water occurs in the liquid form at a temperature of 4 °C. This has the effect that the water at the bottom of lakes in winter typically has a temperature of 4 °C, allowing fish to survive. Another consequence is that ice will melt if sufficient pressure is applied.
Water as a solvent
Water is also a good solvent due to its polarity. When an ionic or polar compound enters water, it is surrounded by water molecules. The relatively small size of water molecules typically allows many water molecules to surround one molecule of solute. The partially negative dipoles of the water are attracted to positively charged components of the solute, and vice versa for the positive dipoles.
In general, ionic and polar substances such as acids, alcohols, and salts are easily soluble in water, and nonpolar substances such as fats and oils are not. Nonpolar molecules stay together in water because it is energetically more favorable for the water molecules to hydrogen bond to each other than to engage in van der Waals interactions with nonpolar molecules.
An example of an ionic solute is table salt; the sodium chloride, NaCl, separates into Na+ cations and Cl- anions, each being surrounded by water molecules. The ions are then easily transported away from their crystalline lattice into solution. An example of a nonionic solute is table sugar. The water dipoles hydrogen bond to the dipolar regions of the sugar molecule and allow it to be carried away into solution.
The solvent properties of water are vital in biology, because many biochemical reactions take place only in solution (e.g., reactions in the cytoplasm and blood).
Cohesion and surface tension
The strong hydrogen bonds give water a high cohesiveness and, consequently, surface tension. This is evident when small quantities of water are put onto a nonsoluble surface and the water stays together as drops. This feature is important when water is carried through xylem up stems in plants; the strong intermolecular attractions hold the water column together, and prevent tension caused by transpiration pull. Other liquids with lower surface tension would have a higher tendency to "rip", forming vacuum or air pockets and rendering the xylem vessel inoperative.
Conductivity
Pure water is actually an insulator, meaning that it does not conduct electricity well. Because water is such a good solvent, it often has some solute dissolved in it, most frequently salt. If water has such impurities, then it can conduct electricity well.
Electrolysis
Water can be split into its constituent elements, hydrogen and oxygen, by passing a current through it. This process is called electrolysis. Water molecules naturally disassociate into H+ and OH- ions, which are pulled toward the cathode and anode, respectively. At the cathode, two H+ ions pick up electrons and form H2 gas. At the anode, four OH- ions combine and release O2 gas, molecular water, and four electrons. The gases produced bubble to the surface, where they can be collected.
Reactivity
Chemically, water is amphoteric: able to act as an acid or base. Occasionally the term hydroxic acid is used when water acts as an acid in a chemical reaction. At a pH of 7 (neutral), the concentration of hydroxide ions (OH-) is equal to that of the hydronium (H3O+) or hydrogen ions (H+) ions. If the equilibrium is disturbed, the solution becomes acidic (higher concentration of hydronium ions) or basic (higher concentration of hydroxide ions).
Purifying water
Purified water is needed for many industrial applications, as well as for consumption. Humans require water that does not contain too much salt or other impurities. Common impurities include chemicals or harmful bacteria. Some solutes are acceptable and even desirable for perceived taste enhancement. Water that is suitable for drinking is termed potable water.
Six popular methods for purifying water are:
- Filtering: Water is passed through a sieve that catches small particles. The tighter the mesh of the sieve, the smaller the particles must be to pass through. Filtering is not sufficient to completely purify water, but it is often a necessary first step, since such particles can interfere with the more thorough purification methods.
- Boiling: Water is heated to its boiling point long enought to inactivate or kill microorganisms that normally live in water at room temperature. Boiling does not remove solutes that have a lower boiling point than the solution, and in fact increases their concentration.
- Carbon filtering: Charcoal, a compound that contains a high concentration of carbon, absorbs many compounds, including toxic compounds. Water is passed through activated charcoal to remove such contaminants. This method is most commonly used in household water filters and fish tanks.
- Distilling: Distillation involves boiling the water to produce water vapor. The water vapor then rises to a cooled surface where it can condense back into a liquid and be collected. Because the solutes are not normally vaporized, they remain in the boiling solution. Even distillation does not completely purify water, because of contaminants with similar boiling points and droplets of unvaporized liquid carried with the steam. Still, 99.9% pure water can be obtained by distillation.
- Reverse osmosis: Mechanical pressure is applied to an impure solution to force pure water through a semi-permeable membrane. The term is reverse osmosis, because normal osmosis would result in pure water moving in the other direction to dilute the impurities. Reverse osmosis is theoretically the most thorough method of large-scale water purification available, although perfect semi-permable membranes are difficult to create.
- Ion exchange chromatography: In this case, water is passed through a charged resin column that has side chains that trap calcium, magnesium, and other heavy metal ions. In many laboratories, this method of purification has replaced distillation, as it provides more quickly a high volume of very pure water. Water purified in this way is called deionized water.
Mythology
Water is one of the four classical elements along with fire, earth and air, and was regarded as the ylem, or basic stuff of the universe. Water was considered cold and moist. In the theory of the four bodily humours, water was asssociated with phlegm.
Water was also one of the Chinese five elements along with air, fire, wood, and metal.
Water rights and development
In the United States water law is divided between two legal doctrines: riparian water rights, used in the eastern and southern states where there is an abundance of water and the appropriation doctrine (or Colorado doctrine) used in the arid western states.
UNESCO's World Water Development Report (WWDR, 2003) from its World Water Assessment Program indicates that in the next 20 years the world is facing an unprecedented lack of drinking water. The quantity of water available to everyone is predicted to decrease by 30%. The causes are contamination, global warming and political problems.
40% of the world's inhabitants have insufficient fresh water for minimal hygiene. More than 2.2 million people died in 2000 from illnesses related to the consumption of contaminated water.
The report indicates large global disparities in the raw volume of available water: from 10 m³ per person per year in Kuwait to 812.121 [m³?] in French Guiana. However, richer countries such as Kuwait can more easily cope with low water availability.
Body of water
See also
- Dehydration
- Drinking water
- Drought
- Flood
- Heavy water
- Hydrography
- Hydrology
- Polywater theory
- Precipitation
- Rain
- Trasvasement
External links
- World Water Forum
- World Water Assessment Program
- United Nations' World Water Development Report
- Mpemba Effect ~ Can hot water freeze faster than cold water?
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Water."
| The following table is compiled from various sources, across various languages. When English abbreviations or acronyms come from a non-English source, this is noted. | |||
| Entry | Source | Expression | Field |
| undw | English | Underwater | Transportation |
Source: compiled by the editor, based on several corpora (additional references). | |||
Synonyms: UnderwaterSynonyms: subaquatic (adj), subaqueous (adj), submerged (adj), submersed (adj). (additional references) |
| Domain | Usage | |
Screenplays | Well don't look now, but the whole town is underwater! (Some Like It Hot; writing credit: Robert Thoeren; M. Logan) Now that you mention it I do have trouble breathing underwater sometimes (Futurama; writing credit: Lance Smith; Carl Colpaert) You'll find that rather difficult to hear underwater. (Diamonds Are Forever; writing credit: Richard Maibaum) | |
Movie/TV Titles | Captain Nemo and the Underwater City (1969) The Underwater City (1962) Assignment Underwater (1960) Underwater! (1955) Living Underwater (1981) | |
Source: compiled by the editor from various references; see credits. | ||
| Domain | Title | ||
Books | |||
Periodicals |
| ||
Theater & Movies | |||
Music |
| ||
High Tech |
| ||
Source: compiled by the editor from various references; see credits. | |||
| Thumbnail | Description & Credit | Thumbnail | Description & Credit |
 | V-fin served as underwater kite to bring sensor close to bottom Housed bottom penetration sonar Deployed off of EXPLORER. Credit: Coast & Geodetic Survey Historical Image Collection. |  | Young snapping turtles being released into the wild. The one on the left is underwater. Credit: America's Coastlines. |
 | Volunteers with the Alliance for the Chesapeake Bay work to restore underwater seagrass beds near Solomons Island. Credit: America's Coastlines. |  | Photo # 1 - Streaming net during trawling operations. Yellow floats are pulled underwater but help keep the mouth of the net open while being towed. Credit: Paths Less Taken - NOAA at the Ends of the Earth. |
 | Photo # 2 - Streaming net during trawling operations. Yellow floats are pulled underwater but help keep the mouth of the net open while being towed. Credit: Paths Less Taken - NOAA at the Ends of the Earth. |  | A single blade of Zostera marina, eelgrass, seen from underwater. Credit: NOAA Restoration Center. |
 | An underwater view of the transplant process. Credit: NOAA Restoration Center. |  | Diver training with a full face mask and underwater communications. Credit: National Undersea Research Program (NURP). |
 | Coral reef chasm frames underwater photographer. Credit: National Undersea Research Program (NURP). |  | Underwater tape recorders were used to record the number and size of each fish species on a set transect. A conversion table was used to convert estimated length of fish to estimated weight. Credit: The Coral Kingdom. |
Source: pictures compiled by the editor from various references; see picture credits. | |||
 |  |
| "Underwater 1" by Eric Ertl Commentary: "Scuba diving in Puerto Rico." | "Underwater Pattern" by Ruben Rodriguez Commentary: "Underwatter pattern with bubbles and reflections." |
Source: photographs selected by the editor, with permission from the photographers. | |
| Play | Caption |
 | Underwater whale communication. |
| Source: compiled by the editor from various references; see credits. | |
| Subject | Topic | Quote |
Health | Infections are rare. The ameba enters the body through the nose and travel to the brain and spinal cord while the person is swimming underwater or diving. (references) | |
Measuring the exact amount of a person's body fat is not easy. The most accurate measures are to weigh a person underwater or to use an X-ray test called Dual Energy X-ray Absorptiometry (DEXA). (references) | ||
Economic History | The Bahamas | The U.S. Navy operates an underwater research facility on Andros Island. (references) |
Cayman Islands | Natural resources: Scenic beaches and underwater attractions, favorable climate. (references) | |
France | Underwater cables are expanding the capacities of terrestrial communications, in addition to those that are developing via satellite. (references) | |
Trade | Mauritius | Imports of the following items are prohibited: ball valve bottles, caps for toy guns, recapped tires, white phosphorous matches, certain firecrackers, kerosene stoves, water scooters, ivory and tortoise shell, underwater fishing guns, candy in the form of cigarettes, toy crash helmets, cigarette papers, used motor vehicle spare parts, electric water heaters with bare elements, portable electric lamps, teething rings, rolling machines (other than industrial-type rolling machines) for cigarette manufacturing, blue asbestos and its products, and items containing chlorofluorocarbons (CFC). A detailed list is available from the Embassy. (references) |
Travel | Ecuador | Travelers to Ecuador's beach areas should be aware that strong currents, undertow, and underwater hazards are common and are not posted. (references) |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
| "Underwater" is generally used as an adjective (general or positive) -- approximately 70.62% of the time. "Underwater" is used about 388 times out of a sample of 100 million words spoken or written in English. Its rank is based on over 700,000 words used in the English language. Some parts-of-speech are not covered due to the samples used by the British National Corpus. (note: percents less than one-hundredth of one percent have been omitted) |
| Parts of Speech | Percent | Usage per 100 Million Words | Rank in English |
| Adjective (general or positive) | 70.62% | 274 | 17,727 |
| Adverb (general) | 29.38% | 114 | 30,294 |
| Total | 100.00% | 388 | N/A |
Source: compiled by the editor from several corpora; see credits.
Expressions using "underwater": nuclear underwater burst ♦ underwater archaeology ♦ underwater archeology ♦ underwater demolition ♦ underwater diver ♦ underwater diving kit ♦ underwater mine. Additional references. | |
| Source: compiled by the editor from various references; see credits. |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Language | Translations for "underwater"; alternative meanings/domain in parentheses. | |
Bulgarian | подводен (subaqueous, submerged, submersed, subsurface, undersea). (various references) | |
Chinese | 水下. (various references) | |
Danish | undersøisk baseret,langtrækkende raketsystem (ULMS, undersea long-range missile system, underwater long-range missile system), SCUBA-lungeautomater for svømmedykkere (SCUBA, self-contained underwater breathing apparatus), mens systemet med den udspaendte traad kraever brug af en wire til mekanisk at give meddelelse om positionen fra havbunden til overfladen,benytter de akustiske systemer lydboelger under vandet som den noedvendige kommunikationsforbindelse (the acoustic systems use underwater sound waves as the required communication link, while the taut line system requires use of a wire to mechanically communicate position from the ocean bottom to the surface), brændselsknipper,som kan identificeres under vand ved hjælp af ultralyd (underwater ultrasonic identifiable seal). (various references) | |
Dutch | onderwater-. (various references) | |
Esperanto | subakva. (various references) | |
Farsi | چیرابی , زیرابزی , زیراب (Drain). (various references) | |
French | système de missiles sous-marins à longue portée (undersea long-range missile system, underwater long-range missile system), sceau identifiable sous l'eau par ultrasons (underwater ultrasonic identifiable seal), appareil respiratoire autonome de plongée (self-contained underwater breathing apparatus), alors que le système à câble tendu requiert l'emploi d'un fil pour transmettre,par voie mécanique,la position du fond marin en surface,les systèmes acoustiques utilisent les ondes sonores sous-marines comme moyen de transmission (the acoustic systems use underwater sound waves as the required communication link). (various references) | |
German | unterwasser (subaqueous, tailwater), unterseeisch (submarine, undersea). (various references) | |
Greek | υπό το ύδωρ, υποβρύχιοσ (subaqueous, submarine), υποβρήχιος. (various references) | |
Hungarian | víz alatti (hydrophone, subaqueous), víz alatt. (various references) | |
Italian | subacqueo (subaqueous), sott'acqua. (various references) | |
Japanese Kanji | 水面下 , 水中 . (various references) | |
Japanese Katakana | すいめんか, すいちゅう. (various references) | |
Korean | 수중. (various references) | |
Manx | fo-honn (submarine). (various references) | |
Pig Latin | erwaterunday.(various references) | |
Portuguese | subaquático (subaqueous, subarctic, subsurface). (various references) | |
Russian | искусный (adroit, artful, daedal, deft, delicate, habile, hackish, handy, ingenious, neat, neat-handed, proficient, skilful, skilled, well-made, workmanlike). (various references) | |
Spanish | submarino (submarine, undersea). (various references) | |
Swedish | undervattens- (submarine, submerged, undersea), under vattnet (undersea). (various references) | |
Turkish | sualtı (submerged, submersed), su altındaki (submerged, sunken). (various references) | |
Turkmen | suwasty. (various references) | |
Ukrainian | підводний (immersed, subaqueous, submarine, undersea), підземна вода. (various references) | |
Vietnamese | làm ở dưới mặt nước, đặt dưới mặt nước, để dùng ở dưới mặt nước. (various references) | |
| Source: compiled by the editor from various translation references. | ||
Misspellings | |
"Underwater" is suggested in spellcheckers for the following: underware. (additional references) | |
| Source: compiled by the editor, based on several corpora (additional references). | |
| # of Phoneme Matches | Pronunciation | Word(s) rhyming with "underwater" (pronounced u"nderwô'ter) |
| 4 | -w ô' t er | backwater, breakwater, deepwater, floodwater, freshwater, headwater, rainwater, Tidewater, wastewater. |
| 3 | -ô' t er | granddaughter, manslaughter, stepdaughter. |
Source: compiled by the editor (additional references); see credits. | ||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "a-d-e-e-n-r-r-t-u-w" | |
-1 letter: renatured, underrate, underwear. | |
-2 letters: denature, renature, returned, underate, undereat, wanderer. | |
-3 letters: daunter, denture, dewater, natured, redrawn, redware, retread, retuned, tarweed, tenured, terrane, treader, unrated, untread, watered, waterer. | |
-4 letters: anteed, ardent, atween, darner, darter, dearer, deewan, derate, drawee, drawer, earned, earner, endear, endure, entera, enured, errand, errant, nature, neared, nearer, neater, neuter, ranted, ranter, reader. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
| 1. Definition 2. Synonyms 3. Crosswords 4. Usage: Modern | 5. Usage: Commercial 6. Images: Slideshow 7. Images: Photo Album 8. Images: Digital Art | 9. Sounds 10. Quotations: Non-fiction 11. Usage Frequency 12. Expressions | 13. Expressions: Internet 14. Translations: Modern 15. Abbreviations 16. Acronyms | 17. Derivations 18. Rhymes 19. Anagrams 20. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
