Sodium-mercury amalgam, reaction with

Interaction of sodium and mercury to form sodium amalgam is violently exothermic, and moderation of the reaction with an inert liquid, or by adding mercury slowly to the sodium is necessary. Even so, temperatures of 400°C may be attained. [Pg.1819]

Elemental sulfur is present in most soils and sediments (especially anaerobic), and is sufficiently soluble in most common organic solvents that the extract should be treated to remove it prior to analysis by ECD-GC or GC-MS. The most effective methods available are (1) reaction with mercury or a mercury amalgam [466] to form mercury sulfide (2) reaction with copper to form copper sulfide or (3) reaction with sodium sulfite in tetrabutyl ammonium hydroxide (Jensen s reagent) [490]. Removal of sulfur with mercury or copper requires the metal surface to be clean and reactive. For small amounts of sulfur, it is possible to include the metal in a clean-up column. However, if the metal surface becomes covered with sulfide, the reaction will cease and it needs to be cleaned with dilute nitric acid. For larger amounts of sulfur, it is more effective to shake the extract with Jensen s reagent [478]. [Pg.68]

Sodium Amalgam. Cover with a large volume of water in a suitable vessel and allow to stand until there is no further reaction. The mercury may then be separated and recovered, and the sodium hydroxide solution washed into the drain.1... [Pg.537]

Alkyl phenyl sulfones (piCj,27) are nearly as acidic as esters hence they are readily deprotonated by n-BuLi, LDA in THF, or EtMgBr in THF to give a-metalated sulfones. Their reaction with aldehydes gives a mixture of diastereomeric P-phenylsul-fone alkoxide adducts. Reductive elimination of the benzenesulfinate moiety from the adduct to produce the alkene is usually slow. To minimize side reactions, the hydroxyl group is first converted to an acetate, benzoate, mesylate, or /7-toluenesul-fonate and then treated with an excess of sodium amalgam [Na(Hg), prepared by adding small pieces of sodium to mercury] in methanol to furnish the trans-dlk n P... [Pg.385]

Observation A flash of light can be observed when the sodium is pressed into the mercury, a dull grey solid matter results which is quite brittle and which can be broken sodium amalgam. In the reaction with water, small bubbles (hydrogen) occur and a solution is produced that colors the indicator paper blue sodium hydroxide solution. Liquid mercury remains after some time, it can be put back into the container. [Pg.134]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...