2811 12 — Hydrogen cyanide "hydrocyanic acid"

2811 Other inorganic acids and compounds of nonmetals with oxygen: - Neophanic acids: 2811 11 - - hydrogen fluoride (fluoric acid) 2811 12 - hydrogen cyanide (hydrogen cyanide) 2811 19 - - other - nonmetal compounds with oxygen inorganic other: 2811 21 - carbon dioxide 2811 22 - silica 2811 29 - other - non-metal compounds with oxygen

This heading covers mineral acids, acid oxides and other non-metal oxides. The most important of these are listed below and are arranged according to their non-metallic component (*). (A) Fluorine compounds (1) Hydrogen fluoride (HF). They are obtained by the action of sulfuric acid on natural calcium fluoride (fluorite) or on cryolite. Purified by treatment with potassium carbonate or distillation (sometimes it contains small amounts of silicates and hexafluorosilic acid as impurities). In the anhydrous state, hydrogen fluoride is a very hygroscopic liquid (boiling point 18 – 20 °C); it “smokes” in a humid atmosphere. In an aqueous state and in a concentrated solution (melvic acid), it burns the skin deeply and charcoal organic materials. It is stored in metal bottles with lead, gutta-percha or ceresin lining, as well as in rubber or plastic vessels; very pure acid is stored in silver bottles. It is used for etching glass, making ash-free filter paper, obtaining tantalum, fluorides, for cleaning and etching foundries, in organic synthesis or to control fermentation processes. (2) Fluorinated acids. These include: (a) tetrafluoroboric acid (fluorobic acid) (HBF4); (b) hexafluorosilicon acid (hydrogen silica) (H2SiF6), for example, in aqueous solutions obtained as by-products in the production of superphosphates or from silicon fluorides. It is used for electrolytic cleaning of tin and lead, for obtaining fluorosilicates, etc.

(*) In the following order: fluorine, chlorine, bromine, iodine, sulfur, selenium, tellurium, nitrogen, phosphorus, arsenic, carbon, silicon.

The most important of these compounds are powerful oxidizing and chlorinating agents used for bleaching and in organic synthesis. They are usually unstable compounds. These include: (1) Chlorine acid (HClO). A product that is dangerous to inhale that explodes when exposed to organic materials. The gas usually exists in aqueous solutions, yellow or sometimes reddish. (2) Chlorine acid (HClO3). This acid exists only as a colorless or yellowish aqueous solution. (3) Chloric acid (HClO4). This product in a more or less concentrated form gives various hydrates. It affects the skin. It is used for analysis. (B) Bromine compounds (1) Hydrogen bromide (HBr). It is a colorless gas with a strong pungent smell. It can be stored under pressure or in the form of aqueous solutions (hydrogen bromide), which slowly decompose in air (especially under the influence of light). Hydrobromic acid is used to produce bromides and in organic synthesis. (2) Bromic acid (HBrO3). It exists only in aqueous solutions; it is used in organic synthesis. (D) iodine compounds (1) Hydrogen iodide (HI). A colorless suffocating, easily decomposing gas. Usually exists in the form of caustic aqueous solutions (hydrogen iodide), which in a concentrated form "smoke" in humid air. Pro is referred to in organic synthesis as a reducing agent or as a medium for fixing iodine. (2) Iodonic acid (HIO3) and its anhydride (I2O5) exist as prismatic crystals or in aqueous solutions. Used in medicine or as an absorbent agent in gas masks. (3) Periodic acid (HIO4•2H2O). It has the same properties as iodine acid. (e) Sulfur compounds (1) Hydrogen sulfide (H2S). A very toxic colorless gas with a fetid smell of rotten eggs. Stored under pressure in steel cylinders or in an aqueous solution (hydrogen sulfide acid). Used in analysis, to purify sulfuric or hydrochloric acids, to obtain sulfur dioxide or regenerated sulfur, etc. (2) Peroxosulphuric acids (super acids) existing in crystalline form: (a) peroxodiseric acid (H2S2O8) and its anhydride (S2O7); (b) peroxomonic sulfuric acid (Caro acid) (H2SO5), has strong hygroscopic and oxidizing properties. (3) Thioacids. Exist only in an aqueous solution: dithionic acid (H 2S2O6); trithionic acid (H 2S3O6); tetrathionic acid (H 2S4O6); pentathionic acid (H2S5O6). (4) Aminosulfonic acid (sulfamic acid) (SO 2(OH)NH2). It turns out the dissolution of urea in sulfuric acid, in sulfur trioxide or oleum; crystalline e substance, insoluble in water, but well soluble in alcohol. Applied in

production of fire-resistant textiles, for tanning, in electroplating and in organic synthesis. (5) Sulfur dioxide (SO2). It is obtained by burning sulfur, by firing natural sulfides (in particular, pyrite) or natural calcium sulfate (for example, anhydrite) with clay and coke. It is a colorless asphyxiating gas. Sulfur dioxide is stored either in a liquefied state under pressure in steel tanks or in an aqueous solution; those sulfur dioxide in an aqueous solution are often incorrectly referred to as "sulphuric acid." As an active reducing and bleaching agent, sulfur dioxide is used, for example, for bleaching animal tissues, straw, feathers or gelatin, in the sulfite process of sugar refining, for preserving fruits and vegetables, for producing hydrosulfites for processing wood pulp, for producing sulfuric acid or as a disinfectant (suspensing fermentation of grape must). Liquid sulfur dioxide, which when evaporating lowers the temperature, is used in refrigeration plants. (6) Sulphur trioxide (sulphur anhydride) (SO 3). White solid needle crystals that look like asbestos. In humid air "smoke"; greedily absorbs water and reacts violently with it. It is stored in airtight vessels made of sheet iron or in glass and ceramic bottles for storing acids equipped with an inorganic absorbent. It is used for oleum (heading 2807) and alum (heading 2833). (7) Diser trioxide (S2O3). Flushing green crystals that decompose upon contact with water and are soluble in alcohol; used as a reducing agent in the production of synthetic dyes. (F) Selenium (1) hydrogen selenide (H2Se). Nauseating gas, dangerous for inhalation, as it causes a violation of the sense of smell. It exists in the form of unstable water solutions. (2) Selenic acid (H2SeO3) and its anhydride (SeO2). Hexagonal white crystals, blurred, well soluble in water, are used in the production of enamels. (3) Selenic acid (H2SeO4). White crystals, anhydrous or hydrated. (G) Telluric compounds These include hydrogen telluride (H2Te) (in aqueous solutions), telluric acid (H2TeO3) and its anhydride (TeO2) (white to ferrous substances), mettelluric acid (H2TeO4) (colorless crystals) and its anhydride (TeO3) (orange solid). (H) Nitrogen compounds (1) Hydrogen azide (hydrogen nitrogen acid) (HN 3). Colorless toxic liquid with a suffocating odor; choir dissolves in water; unstable, has explosive properties. Its salts (azides) are classified in heading 2850 and not in subgroup V. (2) Diazote oxide (nitrogen hemioxide) (N 2O). Sweet gas soluble in water is usually stored in liquid form. In the gas-shaped state, it is used as an anesthetic, and in the liquid and solid states it is used as a refrigerant. (3) Nitrogen dioxide (nitroxil, nitrotic vapors, "nitrogen peroxide") (NO2). At a temperature of 0 ° C is a colorless g idyll, at higher temperatures it becomes

orange-brown in colour; boiling point about 22 °C (giving off red fumes). It is the most stable of the nitrogen oxides. It is a strong oxidising agent. (IJ) PHOSPHORUS COMPOUNDS (1) Phosphinic acid (hypophosphorous acid) (H3PO2). Lamellar crystals melting at about 25 °C, oxidising in air; a powerful reducing agent. (2) Phosphonic acid (phosphorous acid) (H3PO3). Deliquescent crystals melting at about 71 °C, soluble in water. Its anhydride (P2O3 or P4O6) also exists in the form of crystals which melt at about 24 °C and in light turn first yellow, then red, and gradually decompose. (K) ARSENIC COMPOUNDS (1) Diarsenic trioxide (arsenic sesquioxide, arsenious oxide, white arsenic) (As2O3). Sometimes incorrectly called "arsenious acid". Obtained by roasting arsenical ores of nickel or silver, or arsenopyrites. It may contain impurities (arsenic sulphide, sulphur, antimony oxide, etc.). Commercial arsenic trioxide is usually a crystalline white powder, odourless and very poisonous (arsenic bloom). The vitreous oxide takes the form of a transparent amorphous mass; the porcellaneous oxide consists of opaque, interlocked octahedral crystals. It is used for preserving skins or zoological specimens (sometimes mixed with soap), for destroying rats, in the manufacture of fly-papers, for preparing certain glass opacifiers, vitrifiable enamels or mineral greens such as Scheele's green (copper arsenite) or Schweinfurt green (copper acetoarsenite), and in small doses as a medicament (in the treatment of dermatitis, malaria or asthma). (2) Diarsenic pentaoxide (As2O5). Obtained by oxidising arsenic trioxide or by dehydrating arsenic acid; it is a very poisonous white powder which dissolves slowly in water, forming arsenic acid. It is used for the manufacture of arsenic acid, as an oxidising agent, etc. (3) Arsenic acids. "Arsenic acid" is the name given to orthoarsenic acid (H3AsO4·½H2O) and to other hydrates of arsenic pentaoxide (pyro- or metaarsenic acid, etc.). They crystallise in colourless needles and are highly poisonous. Arsenic acid is used in the manufacture of synthetic dyes (fuchsin, etc.), of arsenates and of organic arsenical derivatives used as medicaments or insecticides. This heading excludes arsenic hydrides (e.g., AsH3) (heading 2850). (L) CARBON COMPOUNDS (1) Carbon monoxide (CO). A colourless, odourless, toxic gas. Stored under pressure. Used as a reducing agent, inter alia, in metallurgy. (2) Carbon dioxide (CO2). Sometimes incorrectly called "carbonic acid". Obtained by burning coal, by heating calcareous materials or by treating them with acids.

It is a colourless gas, one and a half times heavier than air; it does not support combustion. Carbon dioxide may be presented either in liquid form (under pressure in steel cylinders) or in solid form (as compressed blocks in insulated containers, "carbon snow" or "dry ice"). It is used in metallurgy, in sugar manufacture and for aerating beverages. In liquid form CO2 is used in brewing, for the preparation of salicylic acid, in fire extinguishers, etc. Solid CO2 is used as a refrigerant (down to – 80 °C). (3) Hydrogen cyanide (hydrocyanic acid, prussic acid) (HCN). Obtained by the action of sulphuric acid on a cyanide or by reacting a mixture of ammonia and hydrocarbons in the presence of catalysts. Hydrogen cyanide is a very toxic colourless liquid with an odour of bitter almonds. It is miscible with water and has a lower density than water. It keeps poorly in dilute solutions and also in the presence of impurities. Hydrocyanic acid is used in organic synthesis (e.g., for the preparation of acrylonitrile by reaction with acetylene) and as a parasiticide. (4) Isocyanic, thiocyanic or fulminic acids. (M) SILICON COMPOUNDS Silicon dioxide (pure silica, silicic anhydride, etc.) (SiO2). Obtained by the action of acids on silicate solutions or by the decomposition of silicon halides with water on heating. It may exist either in amorphous form (as a white powder, "white silica", "flowers of silica", "calcined silica"; as vitreous granules, "transparent quartz glass"; in a gelatinous state, "hydrated silica"), or in crystalline form (tridymite and cristobalite). Silicon dioxide is resistant to acids, and fused silica is therefore used for making laboratory glassware and industrial equipment that can be subjected to sudden changes of temperature (see the General Explanatory Note to Chapter 70). Finely divided silicon dioxide powder is used, for example, as a filler for various kinds of natural and synthetic rubber and other elastomers, as a thickener or thixotropic agent for various plastics, printing ink, paints, coatings and adhesives. Colloidal (pyrogenic) silicon dioxide (obtained by burning silicon tetrachloride or trichlorosilane in hydrogen-oxygen furnaces) is also used in the chemical-mechanical polishing of silicon wafers and as a free-flow agent or anti-settling agent for various materials. Silica fume (obtained as a by-product in the manufacture of silicon, ferrosilicon and zirconium) is also used mainly as a pozzolanic additive in concrete, fibre cement or refractory concretes, and as an additive in polymers. This heading excludes: (a) natural silica, e.g., quartz and kieselguhr (Chapter 25, except for varieties which are precious or semi-precious stones – see the Explanatory Notes to headings 7103 and 7105);

(b) colloidal suspensions of silica are generally classified in heading 3824, except when they are irradiated for other purposes (e.g. processing agents used in the textile industry, heading 3809); (c) silica gel with the addition of cobalt salts (used as a moisture indicator) (heading 3824).

(N) COMPLEX ACIDS This heading also covers complex acids of definite chemical composition consisting of two or more inorganic acids not containing metals (e.g., chloro-acids), or of an acid formed from a non-metal and an acid formed from a metal (e.g., silicotungstic acid or borotungstic acid), not specified or included in other headings of this Chapter. Since in this Nomenclature antimony is a metal, antimonic acid and the antimony oxides fall in heading 2825. Sub-Chapter III HALOGEN OR SULPHUR COMPOUNDS OF NON-METALS GENERAL This sub-Chapter covers products which, although having names (chlorides, sulphides, etc.) similar to those of the metal salts of hydracids falling in Sub-Chapter V, are in fact non-metallic compounds, for example: (1) compounds of a halogen with a non-metal other than oxygen or hydrogen (halide compounds); (2) the same compounds as in item (1), but combined with oxygen (halide oxides); or (3) sulphur with non-metals other than oxygen or hydrogen (sulphur compounds). Non-metal oxide sulphides (sulphur + oxygen + non-metal) are excluded from this sub-Chapter; they fall in heading 2853. Halides, halide oxides and sulphides of metals (see the General Explanatory Note to Sub-Chapter I) or of the ammonium ion (NH4+) fall in Sub-Chapter V, except for compounds of precious metals (heading 2843) and compounds of heading 2844, 2845, 2846 or 2853.

Notes

English text as published in Annex I to Regulation (EU) 2021/1832 (Combined Nomenclature). The EAEU tariff and the EU nomenclature copy these notes from the same convention. For a Russian declaration the binding version is the Russian one: Annex to Decision No 80 of the EEC Council of 14 September 2021.

1. Except where the context otherwise requires, the headings of this chapter apply only to:

(a) separate chemical elements and separate chemically defined compounds, whether or not containing impurities;

(b) the products mentioned in (a) above dissolved in water;

(c) the products mentioned in (a) above dissolved in other solvents provided that the solution constitutes a normal and necessary method of putting up these products adopted solely for reasons of safety or for transport and that the solvent does not render the product particularly suitable for specific use rather than for general use;

(d) the products mentioned in (a), (b) or (c) above with an added stabiliser (including an anti-caking agent) necessary for their preservation or transport;

(e) the products mentioned in (a), (b), (c) or (d) above with an added anti-dusting agent or a colouring substance added to facilitate their identification or for safety reasons, provided that the additions do not render the product particularly suitable for specific use rather than for general use.

2. In addition to dithionites and sulphoxylates, stabilised with organic substances (heading 2831), carbonates and peroxocarbonates of inorganic bases (heading 2836), cyanides, cyanide oxides and complex cyanides of inorganic bases (heading 2837), fulminates, cyanates and thiocyanates, of inorganic bases (heading 2842), organic products included in headings 2843 to 2846 and 2852 and carbides (heading 2849), only the following compounds of carbon are to be classified in this chapter:

(a) oxides of carbon, hydrogen cyanide and fulminic, isocyanic, thiocyanic and other simple or complex cyanogen acids (heading 2811);

(b) halide oxides of carbon (heading 2812);

(c) carbon disulphide (heading 2813);

(d) thiocarbonates, selenocarbonates, tellurocarbonates, selenocyanates, tellurocyanates, tetrathiocyanatodiamminochromates (reineckates) and other complex cyanates, of inorganic bases (heading 2842);

(e) hydrogen peroxide, solidified with urea (heading 2847), carbon oxysulphide, thiocarbonyl halides, cyanogen, cyanogen halides and cyanamide and its metal derivatives (heading 2853) other than calcium cyanamide, whether or not pure (Chapter 31).

3. Subject to the provisions of note 1 to Section VI, this chapter does not cover:

(a) sodium chloride or magnesium oxide, whether or not pure, or other products of Section V;

(b) organo-inorganic compounds other than those mentioned in note 2 above;

(c) products mentioned in note 2, 3, 4 or 5 to Chapter 31;

(d) inorganic products of a kind used as luminophores, of heading 3206; glass frit and other glass in the form of powder, granules or flakes, of heading 3207;

(e) artificial graphite (heading 3801); products put up as charges for fire-extinguishers or put up in fire-extinguishing grenades, of heading 3813; ink removers put up in packings for retail sale, of heading 3824; cultured crystals (other than optical elements) weighing not less than 2,5 g each, of the halides of the alkali or alkaline-earth metals, of heading 3824;

(f) precious or semi-precious stones (natural, synthetic or reconstructed) or dust or powder of such stones (headings 7102 to 7105), or precious metals or precious-metal alloys of Chapter 71;

(g) the metals, whether or not pure, metal alloys or cermets, including sintered metal carbides (metal carbides sintered with a metal), of Section XV; or

(h) optical elements, for example, of the halides of the alkali or alkaline-earth metals (heading 9001).

4. Chemically defined complex acids consisting of a non-metal acid of sub-chapter II and a metal acid of sub-chapter IV are to be classified in heading 2811.

5. Headings 2826 to 2842 apply only to metal or ammonium salts or peroxysalts. Except where the context otherwise requires, double or complex salts are to be classified in heading 2842.

6. Heading 2844 applies only to:

(a) technetium (atomic No 43), promethium (atomic No 61), polonium (atomic No 84) and all elements with an atomic number greater than 84;

(b) natural or artificial radioactive isotopes (including those of the precious metals or of the base metals of Sections XIV and XV), whether or not mixed together;

(c) compounds, inorganic or organic, of these elements or isotopes, whether or not chemically defined, whether or not mixed together;

(d) alloys, dispersions (including cermets), ceramic products and mixtures containing these elements or isotopes or inorganic or organic compounds thereof and having a specific radioactivity exceeding 74 Bq/g (0,002 μCi/g);

(e) spent (irradiated) fuel elements (cartridges) of nuclear reactors;

(f) radioactive residues whether or not usable. The term ‘isotopes’, for the purposes of this note and of the wording of headings 2844 and 2845, refers to: — individual nuclides, excluding, however, those existing in nature in the monoisotopic state, — mixtures of isotopes of one and the same element, enriched in one or several of the said isotopes, that is, elements of which the natural isotopic composition has been artificially modified.

7. Heading 2853 includes copper phosphide (phosphor copper) containing more than 15 % by weight of phosphorus.

8. Chemical elements (for example, silicon and selenium) doped for use in electronics are to be classified in this chapter, provided that they are in forms unworked as drawn, or in the form of cylinders or rods. When cut in the form of discs, wafers or similar forms, they fall in heading 3818.

Subheading note

Machine translation. The original is the Russian text of the EAEU tariff, and customs goes by it; this translation is for understanding only and has no legal force.

1. В субпозиции 2852 10 термин «определенного химического состава» означает все органические или неорганические соединения ртути, удовлетворяющие требованиям примечаний 1 (а) – 1 (д) к группе 28 и примечаний 1 (а) – 1 (з) к группе 29.

Additional note

Machine translation. The original is the Russian text of the EAEU tariff, and customs goes by it; this translation is for understanding only and has no legal force.

1. Unless otherwise specified, the salts referred to in the subheadings include acid salts and basic salts.