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28.53 - Other inorganic compounds (including distilled or conductivity water and water of similar purity); liquid air (whether or not rare gases have been removed); compressed air; amalgams, other than amalgams of precious metals. (A) DISTILLED AND CONDUCTIVITY WATER AND WATER OF SIMILAR PURITY. The heading covers only distilled water, re-distilled or electro-osmotic water, conductivity water and water of similar purity, including water treated with ion exchange media. Natural water, even if filtered, sterilised, purified or softened, is excluded (heading 22.01). When put up as a medicament in measured doses or in packings for retail sale, water falls in heading 30.04. (B) MISCELLANEOUS INORGANIC COMPOUNDS Inor anic chemical products not elsewhere specified or included are also included in this heacfmg (including certain compounds of carbon listed in Chapter Note 2). The heading includes : (I) Cyanogen and halogen compounds of cyanogen, e.g., cyanogen chloride (CNCI) cyanamide and its metal derivatives (other than calcium cyanannde (heading 31.02 or 31.05)). (2) Non-metallic oxysul hides (of arsenic, carbon, silicon) and non-metallic chlorosulphides of hosphorus, car on, etc.). Thiophos ene (CSC12) (thiocarbon 1 chloride, carbon ich orosulphide) obtained by the action o chlorrne on carbon disulp ide, is a red liquid, suffocating and lachrymatory, decomposed by water, used in organic synthesis. !if ! K f (3) Alkali amides. Sodamide or sodium arnide (NaNH2) is obtained by the action of heated ammonia on a sodium-lead alloy, or by passing ammonia in the gaseous state over molten sodium. Pinkish or greenish crystalline masses, decomposed by water. Used in organic synthesis, in the preparation of azides, cyanides, etc. There are also potassium and other metal arnides. (4) Phosphonium iodide. Obtained, for example, by the interaction of phosphorus, iodine and water; it is a reducing agent. (5) Trichlorosilane (SiHC13). Obtained b the reaction of hydrogen chloride (HC1) with silicon, it is used in the manufacture of L e d silica and very pure silicon. (C) LIQUID AIR AND COMPRESSED AIR In commerce, liquefied air is presented in steel or brass vacuum-jacketed containers. It can cause severe burns and renders soft organic materials brittle. It is used for obtaining oxygen, nitrogen and rare gases by fractional distillation. Because of its ra id evaporation, it is used in laboratories as a refrigerating agent. Mixed with charcoal and ot er products it constitutes a powerful explosive used in mming. e This heading also includes : (1) Liquid air fiom which rare gases have been removed. (2) Compressed air. (D) AMALGAMS, EXCEPT AMALGAMS OF PRECIOUS METALS Mercury forms amalgams with several base metals (alkali metals and alkaline-earth metals, zinc, cadmium, antimony, aluminium, tin, copper, lead, bismuth, etc.). Amalgams can be obtained : b direct action of the metals with mercury; by electrolysing the metal salts using a mercury ca ode; or by electrolysing a mercury salt (the cathode being of the metal). X Amal ams obtained by electrolysis and distilled at a low temperature are used to prepare pyrop oric metals more reactive than those obtained at high temperature. They are also used in the metallurgy of precious metals. % (I) Amalgams of alkali metals decompose water with the production of less heat than the pure metals; they are therefore more active reducing agents than the latter. Sodium amalgam is used in the preparation of hydrogen. (2) Aluminium amalgam is used as a reducing agent in organic synthesis. a (3) Cop er amalgam containing a small added quantit of tin is used in dentistry. Co per ama gams are metallic cements, becoming soft when eated, suitable for moulding an for repairing china. P i (4) Zinc amalgam is used in batteries to prevent corrosion. (5) Cadmium amalgam is used in dentistry and in the manufacture of tungsten wire from sintered metal. (6) Antimony-tin amalgam is used for " bronzing " plaster. Amalgams containing precious metals, whether or not associated with base metals, are excluded (heading 28.43). Mercury compounds, whether or not chemically defined, other than amalgams fall in heading 28.52. Harmonized Commodfty Description and Codin9 System fifth edition (LO1 L) VOLUME 2 Sections VI - Vlll Chapters 29 - 43 WOWD CUSTOMS OROAHlZR710~ (fstablished in 1959 as the Customs Co-opration Council) Rue du Marche, 30 6 1210 - B W S S ~ ~ S Telephone +32-2-209.92.1 1 Fax 32-2-209.94.92 + The Customs Co-operation Council * (C.C.C.) was established by a Convention signed in Brussels on 15jh December 1950. Under the terms of that Convention, thefirnctions of the Council are : (a) To study all questions relating to co-operation in customs matters. (b) To examine the technical aspects, as well as the economicfactors related thereto, of customs systems with a view to proposing to its Members practical means of attaining the highest possible degree of harmony and unijormity. (c) To prepare draft Conventions and amendments to Conventions and to recommend their adoption by interested Governments. (d) To make recommendations to ensure the unijom interpretation and application of the Conventions concluded as a result of its work as well as those concerning the Nomenclature for the Classzj?cation of Goods in Customs Tariffs and the Valuation of Goodsfor Customs Purposes and, to this end, to perform suchjknctions as may be expressly assigned to it in those Conventions in accordance with the provisions thereof (e) To make recommendations, in a conciliatory capacity, for the settlement of disputes concerning the * interpretation or application of the Conventions referred to in paragraph (d) above. 03 To ensure the circulation of information regarding customs regulations andprowdures. (g) On its own initiative or on request, to furnish to interested Governments information or advice on customs matters within the general purposes of the present Convention and to make recommendations thereon. @) To co-operate with other inter-governmental organisations as regards matters within its competence. The Councilpossesses juridical personality. * In June 1994 the Council adopted the informal working name "World Customs Organization (WCO) " for the Customs Co-operation Council, in order to indicate more clearly its nature and world-wide status. The Convention establishing the Organization has not been amended, and "Customs Co-operation Council" remains the oflcial name. Copyright O 2006-2012 World Customs Organization (established in 1952 as the Customs Co-operation Council) All rights reserved. Any request regarding translation, reproduction and adaptation of this document should be addressed to couvri~ht~wcoomd.org D/20 1 1/0448/15 ISBN : 978-2-87492-024-0
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.