Silver acetylide

Simple silver acetylide was first prepared by Quet in 1858 even before acetylene itself had been identified. The procedure was based on the introduction of a gas obtained from decomposition of alcohol by electric discharge into an ammoniacal solution of silver chloride [5, 7, 8]. 

In the same year, Vogel and Reischaur obtained silver acetylide by introduction of coal-gas into a solution of the silver salt [9]. The determination of the exact structure of the molecule, however, took a relatively long time. The variety of structures considered and their historical development has been summarized by many authors including, for example, Keiser [7] or Stettbacher [9]. 

Simple silver acetylide is generally quite sensitive to mechanical stimuli and definitely more sensitive than its double salt Ag2C2-AgN03 [2]. Sensitivity of 

Ignition temperatures of silver acetylide reported in various literature sources cover a very broad range spanning from 140 °C to 200 °C. The reason is most likely reflecting different reaction conditions and hence different products. It is therefore very important to always check what was really prepared [12]. The summary of published values of ignition temperatures of silver acetylide in comparison with silver acetylide-silver nitrate is summarized in Table 12.2. 

It was observed by Kohn that the ignition temperature changes as the material ages. Some values determined at heating rate 1 °C s are presented in Table 12.3 for acetylides of silver and copper [12]. The results are the lowest values obtained in a series of measurements. The sensitivity of silver acetylide to impact, friction, and hot wire does not change with time [12]. 

Hazardous properties of some selected acetylides and fulminates are presented in the following sections. 

Structure and reactivity Cu C C Cu, copper salt of weakly acidic acetylene, strong nucleophile 

Cuprous acetylide is used as a diagnostic test to identify the =CH unit to purify acetylene in the preparation of pure copper powder and as a catalyst in the mannfacture of 2-propyn-l-ol and acrylonitrile. 

Red amorphous powder explodes on heating insoluble in water, soluble in acid. 

There are no toxicity data in the published literature on cuprous acetylide. As with many copper salts, inhalation of its dust can cause irritation of the respiratory tract and ulceration of nasal septum. 

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Now add this solution to a jar of acetylene and shake. A yellow-white precipitate of silver acetylide at once forms. 

The cuprous and silver acetylides are both explosive when dry. Therefore when these tests are completed, wash out the gas-jars thoroughly with water. 

Silver Acetylide. Silver acetylide [7659-31-6] (silver carbide), is prepared by bubbling acetylene through an ammoniacal solution of silver... 

Disilver acetylide Silver acetylide-silver nitrate Digold(l) acetylide Barium acetylide Calcium acetylide (carbide)... 

Dicaesium acetylide Copper(ll) acetylide Dicopper(l) acetylide Silver acetylide Caesium acetylide Potassium acetylide Lithium acetylide Sodium acetylide Rubidium acetylide Lithium acetylide-ammonia Dipotassium acetylide Dilithium acetylide Disodium acetylide Dirubidium acetylide Strontium acetylide Silver trifluoromethylacetylide Sodium methoxyacetylide Sodium ethoxyacetylide... 

Security type attache cases incorporating lithium batteries and/or pyrotechnic material Selenium nitride Silver acetylide (dry)... 

SN displacement reactions, 27-9 a-Selenocyclohexanones, 77 Senecioyl chloride, 33 Silmagnesiation, platinum-catalysed, 8 Silametallation of terminal alkynes, 7-9 Silver acetylide, 49 Silver trifluoroacctate, 42,127 Silyl cuprates, 7... 

Silver acetylide decomposition was studied [679] by X-ray diffraction and microscopic measurements and, although the a—time relationship was not established, comparisons of intensities of diffraction lines enabled the value of E to be estimated (170 kj mole 1). The rate-limiting step is believed to involve electron transfer and explosive properties of this compound are attributed to accumulation of solid products which catalyze the decomposition (rather than to thermal deflagration). 

Acetylene can form metal acetylides, e.g. copper or silver acetylide, which on drying become highly explosive service materials require careful selection. 

A line profile analysis of the saturated acetylide surface reveals the buckled nature of the overlayer with a periodicity of seven protrusions or 14 lattice units along the < 110 > axis. The nominal 14 units actually match 13 lattice units therefore to accommodate seven protrusions on 13 lattice units with equal spacing would result in surface buckling (Figure 5.13). The distance between two terminal silver atoms is 5.37 A, which is 2% shorter than that in silver acetylide based on the assumption of covalent radii. 

Silver nitrate (or other soluble salt) reacts with acetylene in presence of ammonia to form silver acetylide, a sensitive and powerful detonator when dry. In the absence of ammonia, or when calcium acetylide is added to silver nitrate solution, explosive double salts of silver acetylide and silver nitrate are produced. Mercury(I) acetylide precipitates silver acetylide from the aqueous nitrate. 

A black solid is produced from these two reagents under influence of ultrasound (but not otherwise) which explodes violently on warming. It is apparently not silver acetylide. 

Silver acetylide is a more powerful detonator than the copper derivative, but both will initiate explosive acetylene-containing gas mixtures [1]. It decomposes violently when heated to 120-140°C [2], Formation of a deposit of this explosive material was observed when silver-containing solutions were aspirated into an acetylene-fuelled atomic absorption spectrometer. Precautions to prevent formation are discussed [3], The effect of ageing for 16 months on the explosive properties of silver and copper acetylides has been studied. Both retain their hazardous properties for many months, and the former is the more effective in initiating acetylene explosions [4],... 

Addition of calcium acetylide to silver nitrate solution precipitates silver acetylide, a highly sensitive explosive. Copper salt solutions would behave similarly. 

Contact with silver nitrate solution transforms copper(I) acetylide into a sensitive and explosive mixture of silver acetylide and silver. 

Silver accumulation, natural defenses against, 22 655 Silver acetate, 22 669 Silver acetylide, 22 670 Silver acetylides, 1 180 Silver alloys, 22 636... 

See Perchloric acid Acetylene, Nitrous oxide See Silver acetylide (reference 3)... 

Kabanov, A. A. etal., Russ. Chem. Rev., 1975, 44, 538-551 Application of electric fields to various explosive heavy metal derivatives (silver oxalate, barium, copper, lead, silver or thallium azides, or silver acetylide) accelerates the rate of thermal decomposition. Possible mechanisms are discussed. 

Silver acetylide-silver nitrate, 0569 Silver azide, 0023... 

Catalytic forms of copper, mercury and silver acetylides, supported on alumina, carbon or silica and used for polymerisation of alkanes, are relatively stable [3], In contact with acetylene, silver and mercury salts will also give explosive acetylides, the mercury derivatives being complex [4], Many of the metal acetylides react violently with oxidants. Impact sensitivities of the dry copper derivatives of acetylene, buten-3-yne and l,3-hexadien-5-yne were determined as 2.4, 2.4 and 4.0 kg m, respectively. The copper derivative of a polyacetylene mixture generated by low-temperature polymerisation of acetylene detonated under 1.2 kg m impact. Sensitivities were much lower for the moist compounds [5], Explosive copper and silver derivatives give non-explosive complexes with trimethyl-, tributyl- or triphenyl-phosphine [6], Formation of silver acetylide on silver-containing solders needs higher acetylene and ammonia concentrations than for formation of copper acetylide. Acetylides are always formed on brass and copper or on silver-containing solders in an atmosphere of acetylene derived from calcium carbide (and which contains traces of phosphine). Silver acetylide is a more efficient explosion initiator than copper acetylide [7],... 

Pentadiyn-l-ylsilver, 1815 Potassium acetylide, 0987 l-Propynylcopper(I), 1098 Rubidium acetylide, 1025 Silver acetylide, 0568... 

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