Definitions
gas [gas]

gas

[gas]
gas, in physics, one of the three commonly recognized states of matter, the other two being solid and liquid. A substance in the gaseous state has neither definite shape nor definite volume. Like liquids, gases are fluids and assume the shape of their containers. Unlike liquids, they will expand to fill any container, regardless of its size. All gases condense into liquids or solids when sufficiently cooled or compressed (see compression; condensation; liquefaction). Most gases first liquefy, but some pass directly into the solid state (see sublimation); carbon dioxide, for example, can condense into dry ice. Some gases are extremely soluble in certain liquids, the liquid absorbing many times its own volume of gas. Some solids, by a process called adsorption, can take up many times their own volume of certain gases. The behavior of gases under various conditions of pressure, temperature, and volume is described by the various gas laws. Many of the properties of gases can be understood by considering the fact that only a small part of the volume of a gas is occupied by its atoms or molecules, which are in rapid, random motion. See kinetic-molecular theory of gases.
gas, fuel, gaseous substance that burns in air and releases enough heat to be useful as a fuel, while also remaining sufficiently stable at ordinary temperatures to permit long-term storage without deterioration or undue hazard. It is advantageous if a fuel gas is readily transportable through pipes and is easily liquefied. Practically all fuel gases meet the first condition, and some meet the second as well. Natural gas, which occurs alone and in conjunction with petroleum deposits, is an excellent fuel gas in wide commercial use. Liquefied petroleum gas is a manufactured mixture of flammable gases that is easily stored in its liquefied condition. Oil gas is a type of gas made by applying heat to various petroleum distillates. Its principal use is as a supplement to natural gas during periods of heavy demand. Coal gas may be any of a variety of gases produced by heating coal in the absence of air and driving off the volatile constituents. It is not as high in fuel value as other gases and often contains tars, light oils, ammonia, and hydrogen sulfide. Producer gas is made by forcing a mixture of air and steam through burning coal or coke. Water gas, or blue gas, which burns with a bright blue flame, is made by passing steam over glowing coke.

Any of a group of substances, most often synthetic organic halogen compounds, that irritate the mucous membranes of the eyes, causing a stinging sensation and tears. They may also irritate the upper respiratory tract, causing coughing, choking, and general debility. Tear gas was first used in warfare in World War I, but since its effects are short-lasting and rarely disabling, it came into use by law-enforcement agencies as a means of dispersing mobs, disabling rioters, and flushing out armed suspects without the use of deadly force.

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or marsh gas

Organic compound, chemical formula CH4, colourless, odourless gas that occurs in natural gas (called firedamp in coal mines) and from bacterial decomposition of vegetation in the absence of oxygen (including in the rumens of cattle and other ruminants and in the gut of termites). The simplest member of the paraffin hydrocarbons, methane burns readily, forming carbon dioxide and water if supplied with enough oxygen for complete combustion or carbon monoxide if the oxygen is insufficient. Mixtures of 5–14percnt methane in air are explosive and have caused many mine disasters. The chief source of methane is natural gas, but it can also be produced from coal. Abundant, cheap, and clean, methane is used widely as a fuel in homes, commercial establishments, and factories; as a safety measure, it is mixed with trace amounts of an odorant to allow its detection. It is also a raw material for many industrial materials, including fertilizers, explosives, chloroform, carbon tetrachloride, and carbon black, and is the principal source of methanol.

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or inert gas

Any of the seven chemical elements that make up the rightmost group of the periodic table as usually arranged: helium, neon, argon, krypton, xenon, radon, and element 118. All are colourless, odourless, and nonflammable and, except for element 118, occur in tiny amounts in the atmosphere (though helium is the most plentiful element in the universe after hydrogen). Their stable electronic configurations, with no unpaired electrons to share, make them extremely unreactive—hence “noble” (i.e., aloof) or inert—though krypton, xenon, and radon, with outer electrons held less firmly, can form compounds (mainly with fluorine). These gases absorb and give off electromagnetic radiation in a much less complex way than other substances, a property exploited in their use in fluorescent lighting devices and discharge lamps. They glow with a characteristic colour when confined in a transparent container at low pressure with an electric current passing through it. Their very low boiling and melting points make them useful as refrigerants for low-temperature research (see cryogenics).

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or ideal gas

Gas whose physical behaviour conforms to the general gas law, which states that for a given quantity of gas, the product of the volume math.V and pressure math.P is proportional to the absolute temperature math.T, or math.Pmath.V = math.kmath.T, where math.k is a constant. A perfect gas is assumed to consist of a large number of molecules in random motion, which obey Newton's laws of motion. Their volume is assumed to be negligibly small, and no forces are presumed to act on the molecules except during momentary collisions. Though no gas has these properties, real gases at sufficiently high temperatures and low pressures can be described this way.

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Colourless, highly flammable gaseous hydrocarbon consisting primarily of methane and ethane. It may also contain heavier hydrocarbons, carbon dioxide, hydrogen, hydrogen sulfide, nitrogen, helium, and argon. It commonly occurs in association with crude oil (see petroleum). Natural gas is extracted from wells drilled into the Earth. Some natural gas can be used as it comes from the well, without any refining, but most requires processing. It is transported either in its natural gaseous state by pipeline or, after liquefaction by cooling, by tankers. Liquefied natural gas occupies only about 1/600 of the volume of the gas. It has grown steadily as a source of energy since the 1930s.

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or laughing gas

Inorganic compound, one of the oxides of nitrogen. A colourless gas with a pleasantly sweetish odour and taste, it has an analgesic effect when inhaled; it is used as an anesthetic (often called just “gas”) in dentistry and surgery. This effect is preceded by mild hysteria, sometimes with laughter, hence the name laughing gas. It is also used as a propellant in food aerosols and as a leak detector.

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Volatile material (mostly swallowed air, partly digestive by-products) in the digestive tract, which normally contains 150–500 cc of gas. Air in the stomach is either belched out or passed to the intestines. Some of its oxygen is absorbed into the blood along the way. Carbon dioxide produced by digestion is added. Nitrogen, the major component, is inert and usually passed on. Obstructions in the small intestine can trap gas in distended pockets, causing severe pain. In the large intestine, bacterial fermentation products are added—mostly hydrogen but also methane, hydrogen sulfide, ammonia, and sulfur-containing mercaptans. Excess gas in the colon is eventually expelled from the body.

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or vapor lamp

Lighting device consisting of a transparent container within which a gas is energized by an applied voltage and made to glow. After practical generators were devised in the 19th century, many experimenters applied electric power to tubes of gas. From circa 1900, electric discharge lamps were in use in Europe and the U.S. Fluorescent, neon, mercury, sodium, and metal-halide lamps are of the electric discharge variety.

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Type of chromatography with a gas mixture as the mobile phase. In a packed column, the packing or solid support (held in a tube) serves as the stationary phase (vapour-phase chromatography, or VPC) or is coated with a liquid stationary phase (gas-liquid chromatography, or GLC). In capillary columns, the stationary phase coats the walls of small-diameter tubes. The sample of gas or volatile liquid to be analyzed is injected into the inlet; its components move through with a carrier gas (usually hydrogen, helium, or argon) at rates influenced by their degree of interaction with the stationary phase. The temperature, nature of the stationary phase, and column length can be varied to improve separation. The gas stream issuing from the column's end may pass through a thermal conductivity detector or a flame ionization detector, where its properties are compared with those of known reference substances. GC is used to measure air pollutants, essential oils, gases or alcohol in blood, and composition of industrial process streams.

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One of the three fundamental states of matter, in which matter has no definite shape, is very fluid, and has a density about 0.1percnt that of liquids. Gas is very compressible but tends to expand indefinitely, and it fills any container. A small change in temperature or pressure produces a substantial change in its volume; these relationships are expressed as equations in the gas laws. The kinetic theory of gases, developed in the 19th century, describes gases as assemblages of tiny particles (atoms or molecules) in constant motion and contributed much to an understanding of their behaviour. The term gas can also mean gasoline, natural gas, or the anesthetic nitrous oxide. Seealso solid.

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Gas is a city in the northwestern part of Allen County, located in southeast Kansas, in the Central United States. The population was 556 at the 2000 census, and it was estimated to be in the year . The city was named for the abundant natural gas that was found in the area.

History

When natural gas was discovered in Elm Township in the summer of 1898 E.K. Taylor sold 60 acres of his farm to some spelter companies and in October sub-divided the remainder into lots, which was the beginning of "Gas City". The place grew rapidly, the cheap fuel afforded by the immense supply of natural gas bringing in a number of large manufacturing plants of various kinds. In 1910 the population was 1,281, and the city had a bank, a daily and a weekly newspaper, an opera house, an international money order postoffice (first opened in August 1899) from which mail was distributed to the surrounding country by rural free delivery, several good mercantile houses, telegraph and express offices.

Geography

Gas is located at (37.923851, -95.346168). Situated along U.S. Route 54 in Elm Township, the city is about three miles east of the city of Iola (the county seat) and 2½ miles west of the city of La Harpe. The interchange between U.S. Routes 54 and 169 is about two miles west of Gas.

According to the United States Census Bureau, the city has a total area of 0.8 square miles (2.0 km²), all of it land.

Demographics

Gas's population was estimated to be in the year .

As of the census of 2000, there were 556 people, 217 households, and 167 families residing in the city. The population density was 735.0 people per square mile (282.5/km²). There were 234 housing units at an average density of 309.4/sq mi (118.9/km²). The racial makeup of the city was 94.60% White, 0.18% African American, 1.26% Native American, 0.72% Asian, 0.18% from other races, and 3.06% from two or more races. Hispanic or Latino of any race were 2.16% of the population.

There were 217 households out of which 34.6% had children under the age of 18 living with them, 65.9% were married couples living together, 7.8% had a female householder with no husband present, and 22.6% were non-families. 20.7% of all households were made up of individuals and 7.8% had someone living alone who was 65 years of age or older. The average household size was 2.56 and the average family size was 2.94.

In the city the population was spread out with 26.6% under the age of 18, 8.5% from 18 to 24, 29.0% from 25 to 44, 23.0% from 45 to 64, and 12.9% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 104.4 males. For every 100 females age 18 and over, there were 96.2 males.

The median income for a household in the city was $35,804, and the median income for a family was $38,942. Males had a median income of $25,104 versus $18,500 for females. The per capita income for the city was $14,012. About 9.4% of families and 12.4% of the population were below the poverty line, including 11.9% of those under age 18 and 10.9% of those age 65 or over.

See also

References

External links

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