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cyanide
A compound containing the –CN group. Organic cyanides are called nitriles. Inorganic cyanides are salts of hydrocyanic acid (HCN), a volatile weak acid; both are highly toxic. Sodium cyanide is made by the Castner process: ammonia is passed through a mixture of carbon and fused sodium. The cyanide ion (CN-) is a pseudohalogen, and forms many complexes. Cyanides are used in the extraction of gold and silver, electroplating and casehardening.
Methane hydrate, for example, is a clathrate in which methane molecules, typically released by bacterial decay, become caged within the open-structured lattice of water ice. It is found commonly in permafrost regions in Siberia and North America and is widespread on the seafloor in the vicinity of continents. The release of methane from these reserves, as the ice melts, has been cited as a potentially significant factor in globally warming. Methane hydrate is also among the clathrate hydrates that have been identified in the ice of cometary nuclei. Quinol is another substance that forms a variety of clathrates with substances such as xenon and sulfur dioxide.
Researchers have begun to investigate silicon and germanium clathrates for possible semiconducting and superconducting properties.
Related categories
• ORGANIC CHEMISTRY
• INORGANIC CHEMISTRY
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