Acetylides silver acetylide

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... 

Under certain circumstances acetylene combines with the metals copper, silver and mercury to form acetylides. As a dry substance these acetylene compounds are explosive and ignite through impact or friction. Compared to the other acetylides, silver acetylide releases the largest amount of energy in an explosion. Acetylides can originate and precipitate from watery saline solutions of the metals mentioned above under certain conditions regarding temperature, pH value and concentration. These precipitation reactions were previously used in the wet chemical acetylene analytics. 

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. 

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. 

When acetylene and real alkynes are in contact with copper, silver and transition metals, they form acetylides and analogues that are explosive, from ambient temperature upwards for acetylides. For instance, acetylene that was accidentally in the presence of electrical wires whose copper was bare led to a detonation. 

Propargyl bromide forms explosive metal acetylides when copper or its alloys, silver or mercury are present. 

The STM study provided microscopic evidence for the participation of added silver atoms in the chemisorbed acetylide structure. The Ag(110)-p(2x 1)0... 

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. 

For equipment handling acetylene the pure metals, or alloys containing copper, silver, mercury, gold, must be avoided to prevent the formation of explosive acetylides. 

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. 

See related HALOACETYLENE DERIVATIVES, METAL ACETYLIDES See other silver compounds... 

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],... 

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