Definition
Natural gas Is a gaseous mineral. It is used in a very wide range as a fuel. But natural gas itself is not used as a fuel; its constituents are isolated from it for separate use.

Natural gas composition
Up to 98% of natural gas is methane, and it also contains methane homologues - ethane, propane and butane. Occasionally, carbon dioxide, hydrogen sulfide and helium may be present. This is the composition of natural gas.

Physical properties
Natural gas is colorless and odorless (if it does not contain hydrogen sulfide), it is lighter than air. Flammable and explosive.
Below are the more detailed properties of natural gas components.

Properties of individual constituents of natural gas (consider the detailed composition of natural gas)

Methane(CH4) is a colorless, odorless gas lighter than air. It is flammable, but it can still be stored fairly easily.

Ethane(C2H6) is a colorless, odorless and colorless gas, slightly heavier than air. Also combustible, but not used as fuel.

Propane(C3H8) is a colorless, odorless gas, poisonous. It has a useful property: propane liquefies at low pressure, which makes it easy to separate it from impurities and transport it.

Butane(C4H10) - similar in properties to propane, but with a higher density. Twice as heavy as air.

Carbon dioxide(CO2) is a colorless, odorless gas with a sour taste. Unlike other components in natural gas (with the exception of helium), carbon dioxide does not burn. Carbon dioxide is one of the least toxic gases.

Helium(He) - colorless, very light (the second of the lightest gases, after hydrogen), colorless and odorless. It is extremely inert and does not react with any of the substances under normal conditions. Does not burn. It is not toxic, but at elevated pressure it can cause anesthesia, like other inert gases.

Hydrogen sulfide(H2S) is a colorless heavy gas with a rotten egg odor. Very poisonous, even at very low concentrations, causes paralysis of the olfactory nerve.
Properties of some other gases that are not part of natural gas, but which have applications close to those of natural gas

Ethylene(C2H4) - Colorless gas with pleasant odor. Its properties are close to ethane, but differs from it in lower density and flammability.

Acetylene(C2H2) is an extremely flammable and explosive colorless gas. It can explode under strong compression. It is not used in the home due to the very high risk of fire or explosion. The main application is in welding.

Application

Methane used as fuel in gas stoves.

Propane and butane- as fuel in some vehicles. Lighters are also filled with liquefied propane.

Ethane rarely used as a fuel, its main application is the production of ethylene.

Ethylene is one of the most produced organic substances in the world. It is a raw material for polyethylene production.

Acetylene used to create very high temperatures in metallurgy (checking and cutting metals). Acetylene It is very flammable, therefore it is not used as fuel in cars, and even without this, the conditions for its storage must be strictly observed.

Hydrogen sulfide, despite its toxicity, is used in small quantities in the so-called. hydrogen sulfide baths. They use some of the antiseptic properties of hydrogen sulfide.

The main useful property helium is its very low density (7 times lighter than air). Balloons and airships are filled with helium. Hydrogen is even lighter than helium, but at the same time flammable. Helium balloons are very popular among children.

Toxicity

Carbon dioxide. Even large amounts of carbon dioxide do not affect human health in any way. However, it interferes with the absorption of oxygen when the content in the atmosphere is from 3% to 10% by volume. With such concentration, suffocation and even death begins.

Helium. Helium is completely non-toxic under normal conditions due to its inertness. But with increased pressure, an initial stage of anesthesia occurs, similar to the effect of laughing gas *.

Hydrogen sulfide... The toxic properties of this gas are great. With prolonged exposure to the sense of smell, dizziness, vomiting occurs. The olfactory nerve is also paralyzed, so there is an illusion of the absence of hydrogen sulfide, but in fact the body simply does not feel it. Hydrogen sulfide poisoning occurs at a concentration of 0.2–0.3 mg / m3, a concentration above 1 mg / m3 is fatal.

Combustion process
All hydrocarbons under complete oxidation (excess oxygen) release carbon dioxide and water. For example:
CH4 + 3O2 = CO2 + 2H2O
If incomplete (lack of oxygen) - carbon monoxide and water:
2CH4 + 6O2 = 2CO + 4H2O
With an even smaller amount of oxygen, finely dispersed carbon (soot) is released:
CH4 + O2 = C + 2H2O.
Methane burns with a blue flame, ethane - almost colorless like alcohol, propane and butane - yellow, ethylene - luminous, carbon monoxide - light blue. Acetylene - yellowish, heavily smoky. If you have a gas stove at home and instead of the usual blue flame you see a yellow one, you should know that methane is diluted with propane.

Notes (edit)

Helium, unlike any other gas, does not exist in a solid state.
Laughing gas Is the trivial name for nitrous oxide N2O.

Comments and additions to the article are in the comments.

Noun., M., Uptr. cf. often Morphology: (no) what? gas and gas, why? gas, (see) what? gas, what? gas, about what? about gas and gas; pl. what? gases, (no) what? gases, why? gases, (see) what? gases, what? gases, about what? about gases 1. Gas is ... ... Dmitriev's Explanatory Dictionary

COLORLESS- COLORLESS, colorless, colorless; colorless, colorless, colorless. 1. Does not have color, coloration. Colorless gas. 2. transfer. Dull, unremarkable, unoriginal. Colorless style. Ushakov's explanatory dictionary. D.N. Ushakov. 1935 1940 ... Ushakov's Explanatory Dictionary

colorless- oh, oh; ten, tna, tno. 1. It has no color, pronounced coloration. B. gas. Used liquid. B. varnish. Big eyes, hair. Big face. 2. Deprived of originality, expressiveness; unremarkable, ordinary. B. story. B th role. Good life. ◁ ... ... encyclopedic Dictionary

colorless- oh, oh; ten, tna, tno. see also. colorless, colorless 1) Colorless, pronounced coloration. Colorless gas. Used liquid. Colorless varnish. Used ... Dictionary of many expressions

Carbon Dioxide, Carbon Dioxide Gas- a colorless gas formed in tissues as a result of metabolism and carried with the bloodstream into the lungs, from where it is exhaled during respiration (an increase in the concentration of this gas in the blood stimulates the respiration process). Carbon dioxide in small amounts ... ... Medical terms

Carbon monoxide- Carbon monoxide General Systematic name Carbon monoxide Chemical formula ... Wikipedia

Laughing gas- Nitric oxide (I) General Systematic name Nitric oxide (I) Chemical formula N2O Rel. molecule weight 44 a. e. m ... Wikipedia

Swamp gas or methane- (also hydrogenous methyl, form) a saturated hydrocarbon of the composition CH4, the first member of the series CnH2n + n, one of the simplest carbon compounds around which all the others are grouped and from which they can be produced through the substitution of atoms ... ... Encyclopedic Dictionary of F.A. Brockhaus and I.A. Efron

Carbon dioxide- Carbon dioxide Other names carbon dioxide, carbon dioxide, dry ice (solid) Formula CO2 Molar ... Wikipedia

STO Gazprom 5.12-2008: Combustible natural gas. Determination of sulfur-containing components by chromatographic method- Terminology STO Gazprom 5.12 2008: Combustible natural gas. Determination of sulfur-containing components by chromatography: carbonyl sulphide COS: A toxic colorless gas sometimes present in GGP. Definitions of the term from various documents: ... ... Dictionary-reference book of terms of normative and technical documentation

Carbon dioxide- carbon dioxide (a. carbon dioxide; n. Kohlensaure, gasformige Kohlensaure, Kohlendioxyd; f. gaz carbonique; and. gas carbonico), coal anhydride to you (CO2). U. g. Colorless gas with slightly acidic taste and smell; density is relatively ... ... Geological encyclopedia

Liquid and gaseous. Almost any liquid can acquire each of the other two. Many solids, when melted, evaporated, or burned, can replenish the contents of the air. But not every gas can become a component of solids or liquids. Various types of gases are known, which differ from each other in properties, origin and application characteristics.

Definition and properties

Gas is a substance that is characterized by the absence or minimum value of intermolecular bonds, as well as the active mobility of particles. The main properties that all types of gases have:

1. Fluidity, deformability, volatility, the desire for maximum volume, the reaction of atoms and molecules to a decrease or increase in temperature, which is manifested by a change in the intensity of their movement.
2. They exist at a temperature in which an increase in pressure does not lead to a transition to a liquid state.
3. Easily shrink, shrinking. This makes it easy to transport and use.
4. Most are liquefied by compression within certain limits of pressures and critical values ​​of heat.

Due to the inaccessibility of research, they are described using the following basic parameters: temperature, pressure, volume, molar mass.

Field classification

In the natural environment, all types of gases are found in air, earth and water.

1. Air constituents: oxygen, nitrogen, carbon dioxide, argon, nitrogen oxide with impurities of neon, krypton, hydrogen, methane.
2. In the earth's crust, nitrogen, hydrogen, methane and other hydrocarbons, carbon dioxide, sulfur oxide and others are in a gaseous and liquid state. There are also gas deposits in the solid fraction mixed with water reservoirs at pressures of about 250 atm. at relatively low temperatures (up to 20˚С).
3. The reservoirs contain soluble gases - hydrogen chloride, ammonia and poorly soluble - oxygen, nitrogen, hydrogen, carbon dioxide, etc.

Natural reserves far exceed the possible amount of artificially created ones.

Flammability classification

All types of gases, depending on the behavioral characteristics in the processes of ignition and combustion, are divided into oxidizing agents, inert and combustible.

1. Oxidants promote combustion and support combustion, but do not burn themselves: air, oxygen, fluorine, chlorine, oxide and nitrogen dioxide.
2. Inert ones do not participate in combustion, however, they tend to displace oxygen and affect a decrease in the intensity of the process: helium, neon, xenon, nitrogen, argon,
3. Combustible materials ignite or explode when combined with oxygen: methane, ammonia, hydrogen, acetylene, propane, butane, ethane, ethylene. Most of them are characterized by combustion only under conditions of a certain composition of the gas mixture. Due to this property, gas is the most widespread type of fuel today. Methane, propane, butane are used in this capacity.

Carbon dioxide and its role

It is one of the most common gases in the atmosphere (0.04%). At normal temperature and atmospheric pressure, it has a density of 1.98 kg / m 3. It can be in solid and liquid state. The solid phase occurs at negative heat values ​​and constant atmospheric pressure, it is called "dry ice". The liquid phase of CO 2 is possible with increasing pressure. This property is used for storage, transportation and technological applications. Sublimation (transition to a gaseous state from a solid, without an intermediate liquid phase) is possible at -77 - -79˚С. Solubility in water in a ratio of 1: 1 is realized at t = 14-16˚С.

The types of carbon dioxide are distinguished according to their origin:

1. Waste products of plants and animals, volcanic emissions, gas emissions from the bowels of the earth, evaporation from the surface of water bodies.
2. The results of human activities, including emissions from the combustion of all types of fuels.

As a useful substance, it is used:

1. In carbon dioxide fire extinguishers.
2. In cylinders for arc welding in a suitable CO2 environment.
3. In the food industry as a preservative and for carbonating water.
4. As a coolant for temporary cooling.
5. In the chemical industry.
6. In metallurgy.

Being an indispensable component of the life of the planet, man, the operation of machines and entire factories, it accumulates in the lower and upper layers of the atmosphere, delaying the release of heat and creating a "greenhouse effect".

and his role

Among the substances of natural origin and technological purpose, there are those that have a high degree of combustibility and calorific value. The following types of liquefied gas are used for storage, transportation and use: methane, propane, butane, as well as propane-butane mixtures.

Butane (C 4 H 10) and propane are components of petroleum gases. The first one liquefies at -1 - -0.5˚С. Pure butane is not transported and used in frosty weather due to its freezing. The liquefaction temperature for propane (C 3 H 8) is -41 - -42˚C, the critical pressure is 4.27 MPa.

Methane (CH 4) - the main component. Types of gas source - oil deposits, products of biogenic processes. Liquefaction occurs with the help of stage-by-stage compression and heat reduction to -160 - -161˚С. At each stage, it is compressed 5-10 times.

Liquefaction is carried out in special factories. Propane, butane and their mixtures are produced separately for domestic and industrial use. Methane is used in industry and as a fuel for transport. The latter can also be produced in a compressed form.

Compressed gas and its role

Recently, compressed natural gas has gained popularity. If only liquefaction is used for propane and butane, then methane can be produced in both liquefied and compressed state. Gas in cylinders under a high pressure of 20 MPa has a number of advantages over the well-known liquefied gas.

1. High evaporation rate, including at negative air temperatures, absence of negative accumulation phenomena.
2. Lower level of toxicity.
3. Complete combustion, high efficiency, no negative impact on equipment and atmosphere.

Increasingly, it is used not only for trucks, but also for cars, as well as for boiler equipment.

Gas is an inconspicuous, but irreplaceable substance for human life. The high calorific value of some of them justifies the widespread use of various components of natural gas as fuel for industry and transport.

Gases are perhaps the most dangerous poisonous substances. Most of them are odorless and colorless, and therefore it is not immediately possible to recognize the effect of a substance. In order to avoid negative consequences, you need to know which gases are the most poisonous, the symptoms that arise when exposed to them, as well as first aid.

Among the poisonous substances, gases are the most insidious. Unlike liquids and solids, they spread throughout the volume of the room, and this spread has no boundaries. Very often, the poisonous gas has neither color nor smell, its presence can be the result of someone's negligence or malicious intent, and it is not immediately possible to find out about poisoning. Knowledge of the characteristics of such poisons, compliance with safety regulations and civil defense standards, as well as the ability to provide first aid are the key to your safety.

The concepts of "poisonous gas" and "gas as an aggregate state of matter" in physics and chemistry are somewhat different.

So, among the former include various aerosols and volatile liquids, the evaporation temperature of which is within the "comfortable" conditions for humans.

Such toxic substances can be classified in two ways - according to their purpose and principle of action.

Practical use

Oddly enough, but most of these substances are not at all intended to poison someone. They have a completely legitimate application and are actively used in the economy. So, according to the criterion of use, they can be divided into:

• (BOV);
• substances used in industry and in everyday life;
• by-products of chemical reactions.

The first group includes gases and aerosols: hydrocyanic acid, cyanogen chloride, mustard gas, sarin, and a number of other phosphorus compounds. The second includes chlorine, ammonia, various disinfestation agents, and the third includes hydrogen sulfide, carbon monoxide, nitric oxides (all of which are poisonous).

Operating principle

The toxicity of any substance manifests itself in different ways, and gases are no exception. Symptoms caused by the ingress of a poisonous gas into the body vary significantly. The following groups are distinguished according to the principle of action:

• nerve paralysis, that is, causing general or local paralysis;
• skin blisters, destroying the skin;
• suffocating;
• lacrimal;
• psychotomimetic;
• irritating mucous membranes;
• general toxicity.

Some have complex effects on the body.

Characteristics of toxic substances

To distinguish toxic substances from each other, one should know their physical and chemical properties. The likelihood of finding a substance in a particular place and its concentration are also of great importance. The possibility of a lethal outcome from the action of a poisonous gas depends on the latter. Some of their properties are indicated in the table-list.

Where danger awaits

The BOV category includes such substances as sarin, mustard gas, phosgene, adamsite, cyanogen chlorine, lewisite, hydrocyanic acid, chloroacetophenone, CS, CR, soman, VX, CX, diphenylcyanarsine, chloropicrin. They are included in the lists of prohibited for use during hostilities, but, apparently, in some military units there are. This is evidenced by the fact that in the courses on civil defense and school life safety, they still teach the skills of putting on a gas mask, and in military units - chemical protection suits (OZK). Antidotes to a number of BOV are included in military first-aid kits.

Some of the BOV have quite peaceful applications. For example:

• phosgene is used for the production of dyes and polycarbonate;
• hydrocyanic acid and its derivatives - in the mining industry, in the production of plastics, as a herbicide;

Chlorine gas is used as a disinfectant, so barrels with a green stripe where it is stored are located in enterprises dealing with centralized water supply.

Hydrogen sulfide is produced in small quantities by living organisms, and is also formed during their decomposition. Found its place in the chemical industry and medicine - hydrogen sulfide baths are one of the components of rehabilitation for certain diseases.

It is also produced at factories, and it goes to the production of mineral fertilizers, mixtures for gas generators. But in everyday life it is not needed and is a by-product of human activity. It is contained in vehicle exhaust and is formed by improper operation of heating devices.

Forms of issue

The chapter with this title is dedicated to those who like to walk through abandoned factories, military units and climb where they should not. Before you open the package with some letters and numbers, you should at least find out their decoding.

I must say, it is not always the same. Different industries have adopted different labeling systems, and there is nothing to say about the standards of other countries. But there is one universal designation for poisons, and it looks like this:

The triangle may not exist, but the skull is a must when it comes to storage containers. There may also be warnings with the words "fatal" and "fatal". Combat units may not contain it, after all, they are not created for decoration.

If you're out of luck

In most cases, gas poisoning is an exceptional event. In the old days, people lived with stove heating, and this happened more often; later, when poisoning substances found their use in warfare, such poisoning became a problem, and by now most countries have ratified the Convention on the Non-Use of Chemical Weapons. But an agreement is one thing, and practice is quite another. People, due to various circumstances, continue to die.

If you come into contact with poisonous gas, you should be alerted by one of the following signs:

If you find any signs in yourself, immediately consult a doctor; some gases can paralyze you in a relatively short time.

Timely administration of antidote and first aid will allow you to save your life and at least the rest of your health.