Reactive alkali atoms, thermal

Sodium [7440-23-5] Na, an alkali metal, is the second element of Group 1 (lA) of the Periodic Table, atomic wt 22.9898. The chemical symbol is derived from the Latin natrium. Commercial iaterest ia the metal derives from its high chemical reactivity, low melting poiat, high boiling poiat, good thermal and electrical conductivity, and high value ia use. 

At ordinary temperatures the oxidation and hydrolysis of ethyl chloride take place slowly. In (he absence of air and water, it can be used with most common metals up to 200°C (392 F). Ethyl chloride burns with a green-edged flame, producing hydrogen chloride, carbon dioxide and water. It is thermally stable to 400 C (752 F) thermal flitting yields ethylene and hydrogen chloride. The reactivity of ethyl chloride as an intermediate is often based on the affinity of alkali metal atoms for its chlorine atom. 

Polyisobutene is non-crystalline when unstretched and is therefore soluble at room temperature in hydrocarbons and halogenated hydrocarbons. The material is resistant to most acids, alkalis and aqueous solutions, as would be expected from its saturated hydrocarbon structure and absence of tertiary hydrogen atoms. The lack of tertiary hydrogen atoms renders polyisobutene more resistant to oxidation than polypropylene also, the less numerous and partially shielded methylene groups in polyisobutene are less reactive than those in polyethylene. However, polyisobutene is rather susceptible to thermal degradation since chain scission is favoured by the greater stability of the resultant tertiary free radical ... 

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