List of deadly poisonous gases and their effects on humans. Main types of gases Definition and properties

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

Definition and properties

A 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:

Fluidity, deformability, volatility, striving 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.
They exist at a temperature at which an increase in pressure does not lead to a transition to a liquid state.
Easily compressed, decreasing in volume. This simplifies transport and use.
Most are liquefied by compression within certain limits of pressure and critical heat values.

Due to the research inaccessibility, 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, land and water.

Air components: oxygen, nitrogen, carbon dioxide, argon, nitric oxide with admixtures of neon, krypton, hydrogen, methane.
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 layers at pressures of about 250 atm. at relatively low temperatures (up to 20˚С).
Reservoirs contain soluble gases - hydrogen chloride, ammonia and poorly soluble gases - oxygen, nitrogen, hydrogen, carbon dioxide, etc.

Natural reserves far exceed the possible number 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 oxidizers, inert and combustible.

Oxidizing agents promote combustion and support combustion, but do not burn themselves: air, oxygen, fluorine, chlorine, nitrogen oxide and dioxide.
Inert ones do not participate in combustion, however, they tend to displace oxygen and influence the decrease in the intensity of the process: helium, neon, xenon, nitrogen, argon,
Combustibles 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 type of fuel, by far the most common. In this capacity, methane, propane, butane are used.

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. May be in solid or liquid state. The solid phase occurs at negative heat 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 the ratio 1:1 is realized at t=14-16˚С.

Types of carbon dioxide are distinguished depending on the origin:

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

As a useful substance, it is used:

in carbon dioxide fire extinguishers.
In cylinders for arc welding in a suitable CO 2 environment.
In the food industry as a preservative and for carbonation of water.
As a refrigerant for temporary cooling.
in the chemical industry.
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 substances of natural origin and technological purposes, there are those that have a high degree of flammability 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. Transportation and use in frosty weather of pure butane is not carried out due to its freezing. Liquefaction temperature for propane (C 3 H 8) -41 - -42˚C, critical pressure - 4.27 MPa.

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

Liquefaction is carried out in special plants. Propane, butane, as well as their mixture for domestic and industrial use are produced separately. Methane is used in industry and as a fuel for transport. The latter can also be issued in 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 both in a liquefied and in a compressed state. Gas in cylinders under high pressure of 20 MPa has a number of advantages over the well-known liquefied one.

High evaporation rate, including at negative air temperatures, absence of negative accumulation phenomena.
Lower level of toxicity.
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 indispensable substance for human life. The high calorific value of some of them justifies the widespread use of various components of natural gas as a fuel for industry and transport.

Definition
Natural gas is a mineral in the gaseous state. It is widely used as a fuel. But natural gas itself is not used as a fuel, its components are separated from it for separate use.

Composition of natural gas
Up to 98% of natural gas is methane, it also includes methane homologues - ethane, propane and butane. Sometimes 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 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. Flammable, but still it can be stored with sufficient ease.

Ethane(C2H6) is a colorless, odorless and colorless gas, slightly heavier than air. Also combustible, but not used as a 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 has a higher density. Twice as heavy as air.

Carbon dioxide(CO2) is a colorless, odorless gas with a sour taste. Unlike the other components of 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) without color and odor. Extremely inert, under normal conditions does not react with any of the substances. 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 smell of rotten eggs. Very poisonous, even at very low concentrations it causes paralysis of the olfactory nerve.
Properties of certain other gases that are not part of natural gas but have uses similar to those of natural gas

Ethylene(C2H4) - A colorless gas with a pleasant smell. It is similar in properties to ethane, but differs from it in lower density and flammability.

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

Application

Methane used as fuel in gas stoves.

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

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

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

Acetylene used to create a very high temperature in metallurgy (reconciliation and cutting of metals). Acetylene it is very combustible, therefore it is not used as a 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. 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). Helium fill balloons and airships. Hydrogen is even lighter than helium, but at the same time combustible. 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 prevents the absorption of oxygen when the content in the atmosphere is from 3% to 10% by volume. At this concentration, suffocation and even death begin.

Helium. Helium is completely non-toxic under normal conditions due to its inertness. But with increased pressure, the 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 and vomiting occur. 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 anymore. 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, when fully oxidized (excess oxygen), release carbon dioxide and water. For example:
CH4 + 3O2 = CO2 + 2H2O
With 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, strongly smokes. If you have a gas stove at home and instead of the usual blue flame you see yellow, you should know that methane is diluted with propane.

Notes

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 - in the comments.

Gases are perhaps the most dangerous toxic 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, it is necessary to know which gases are the most toxic, the symptoms that occur when exposed to them, as well as first aid.

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

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

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

There are two ways to classify such toxic substances - according to 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 the following gases and aerosols: hydrocyanic acid, cyanogen chloride, mustard gas, sarin and a number of other phosphorus compounds. The second group includes chlorine, ammonia, various pest control agents, and the third group includes hydrogen sulfide, carbon monoxide, nitrogen oxides (all of them are poisonous).

Operating principle

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

nerve paralytic, that is, causing general or local paralysis;
skin-abscesses, destroying the skin;
suffocating;
tear;
psychotomimetic;
irritating mucous membranes;
general toxicity.

Some have a complex effect on the body.

Characteristics of toxic substances

To distinguish toxic substances from each other, one should know their physical and chemical properties. The probability of finding a substance in a particular place and its concentration are also of considerable importance. The possibility of death from the action of poisonous gas depends on the latter. The list-table shows some of their properties.

poisonous substance	chemical formula	physical properties	operating principle	lethal concentration
chlorine	Cl2	yellow-green gas with a sweetish odor, heavier than air	suffocating, forms hydrochloric acid when inhaled	6 mg/m3
	C4H10FO2P	Colorless and odorless liquid, volatile at 20 degrees	nerve gas	70 mg/m3 for 1 minute of breathing
mustard gas	C4H8Cl2S	Colorless liquid with garlic or mustard odor	blistering, destroys cell membranes; very aggressive	in any quantity
carbon monoxide, carbon monoxide (II), carbon monoxide	CO	colorless and odorless toxic gas	general toxic, interferes with the supply of oxygen to organs	29 mg/m3
phosgene	COCl2	colorless poisonous gas with the smell of rotten hay	suffocating	4 mg/m3
nitric oxide (IV)	NO	brown gas, industrial waste	suffocating, forms nitric acid in the lungs	40 mg/m3
hydrocyanic acid	HCN	colorless, evaporates at 26 degrees	general toxic, blocks the supply of oxygen to tissues	11 mg/m3
adamsite	C12H19AsClN	yellow powder, applied as an aerosol	irritant to mucous membranes	1 gr per person
BZ	C21H23NO3	colorless crystals, sprayable	psychomimetic BOV, causes acute psychosis with hallucinations	not identified, the effect is relevant for 80 hours when taken at 1 mg per person
bromobenzyl cyanide	C8H6BrN	colorless liquid	tear	4 in 2 minutes
lewisite	C2H2AsCl3	brown liquid with a pungent geranium odor	blistering and general toxic	5-10 mg per kg of body weight
hydrogen sulfide	H2S	rotten egg odor gas	general toxic and nerve-paralytic	0,1%
cyanogen chloride	ClCN	colorless gas with a pungent odor	general toxic, similar to the action of hydrocyanic acid, pierces the gas mask filter	0.4 mg/l, death within 1 minute

Where danger awaits

The CWA category includes substances such as sarin, mustard gas, phosgene, adamsite, cyanogen chloride, lewisite, hydrocyanic acid, chloroacetophenone, CS, CR, soman, VX, CX, diphenyl cyanarsine, chloropicrin. They are listed as prohibited for use during hostilities, but, apparently, some military units have them. This is also evidenced by the fact that the skills of putting on a gas mask are still taught in courses on civil defense and school life safety, and in military units - chemical protection suits (OZK). Antidotes for a number of BOVs are part of military first-aid kits.

Some of the BOVs have quite peaceful uses. For example:

phosgene is used to make 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 at enterprises engaged in centralized water supply.

Hydrogen sulfide is produced in small quantities by living organisms, and is also formed during their decomposition. Has 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 enterprises, 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 found in the exhaust of vehicles and is formed during improper operation of heating devices.

Release form

A chapter with this title is dedicated to those who like to walk around abandoned factories, military units and go where they shouldn't. Before you open the packaging with some letters and numbers, you should at least find out their decoding.

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

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

BOV	Russian marking	american labeling	release form	note
sarin	R-35	GB	metal drums and containers for use in the size of a thermos, glass beads	sometimes you can find the name T-144 and T-46 (trilon)
soman	R-55	GD	similar barrels and shells
vee gas	VR	VX-GAS	barrels, projectiles	used as a pesticide
hydrocyanic acid	usually write the chemical formula	AC	various plastic containers and other neutral material	used as a disinfectant
cyanogen chloride	used in industry, write the name and formula	CK	large tanks, pressurized	pesticide and paint making agent
cyanogen bromide	similar to cyanogen chloride		in dry form (powder), as it is explosive
phosgene	R-10	CG	barrels and cylinders
diphosgene		D.P.	tanks and cylinders - intermediate packaging only	used in the production of phosgene
mustard gas	R-5, VR-16	H, HD, VV	barrels and shells of various sizes
nitrogen mustard		HN	barrels, projectiles
lewisite	R-43	L	barrels, tanks	used for production
diphenylchlorarsine		DA	in World War I it was used in bombs, barrels and gas machines	another name - Clark I
adamsite	R-15	DM	barrels	possibly lie at the bottom of the Baltic Sea
lilac	lilac	CS	spray cans	is on free sale
dibenzoxazepine	algogen	CR	spray cans	sold in the store as personal protective equipment
chloroacetophenone	bird cherry	CN	balloons, balloons, smoke bombs
bromobenzyl cyanide	kamit	CA		not applied since World War I
chloropicrin	nitrochloroform		plastic container	agricultural pesticide, poison
BZ	R-78	BZ	powder; application – via aerosol generator	exists in the form of aviation cassettes

If you're out of luck

In most cases, gassing is an exceptional event. In the old days, people lived with stove heating, and this happened more often; later, when poisonous substances found their way into warfare, such poisoning became a problem, and by now most countries have ratified the convention on the non-use of chemical weapons. But the contract is one thing, and the practice is quite another. People continue to die for various reasons.

When exposed to poisonous gas, one of the following signs should alert you:

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

The timely introduction of an antidote and first aid will allow you to save your life and at least the remnants of health.

Exist., m., use. comp. often Morphology: (no) what? gas and gas, why? gas, (see) what? gas what? gas, what? about gas and on gas; pl. what? gases, (no) what? gases, why? gases, (see) what? gases, what? gases, what? about gases 1. Gas is ... ... Dictionary of Dmitriev

COLORLESS- COLORLESS, colorless, colorless; colorless, colorless, colorless. 1. Having no color, coloring. colorless gas. 2. trans. Unremarkable, unremarkable, unoriginal. Colorless style. Explanatory Dictionary of Ushakov. D.N. Ushakov. 1935 1940 ... Explanatory Dictionary of Ushakov

colorless- oh, oh; ten, tna, tno. 1. Having no color, pronounced color. B. gas. Second liquid. B. varnish. Used eyes, hair. Whoa face. 2. Deprived of originality, expressiveness; unremarkable, unremarkable. B. story. Second role. Whoa life. ◁… … encyclopedic Dictionary

colorless- oh, oh; ten, tna, tno. see also colorless, colorless 1) Having no color, pronounced color. Colorless gas. Second liquid. Colorless/tny varnish. B s… Dictionary of many expressions

Carbon Dioxide, Carbon Dioxide Gas- a colorless gas formed in the tissues as a result of metabolism and carried with the bloodstream to the lungs, from where it is exhaled when breathing (an increase in the concentration of this gas in the blood stimulates the breathing process). Small amounts of carbon dioxide ... ... 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. molek. weight 44 a. e. m ... Wikipedia

Marsh gas or methane- (also methyl hydrogen, formene) saturated hydrocarbon of composition CH4, the first member of the CnH2n + n series, one of the simplest carbon compounds around which all the others are grouped and from which can be produced through the substitution of atoms ... ... Encyclopedic Dictionary 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 sulfide COS: Toxic, colorless gas, sometimes present in HGP. 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), carbonic anhydride (CO2). U. g. colorless gas with a slightly acidic taste and odor; density relative to ... ... Geological Encyclopedia