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| Names | |
|---|---|
| Other names Disodium telluride; hydrotelluric acid, sodium salt | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
| ECHA InfoCard | 100.031.629 |
| EC Number |
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| Properties | |
| Na2Te | |
| Molar mass | 173.58 g/mol |
| Appearance | white powder, hygroscopic |
| Density | 2.90 g/cm3, solid |
| Melting point | 953 °C (1,747 °F; 1,226 K) |
| very soluble | |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | In contact with water releases flammable gas |
| GHS labelling:[1] | |
  | |
| Warning | |
| H261,H302+H312+H332,H315,H319 | |
| P261,P264,P270,P271,P280,P302+P352,P304+P340,P305+P351+P338,P312,P330,P335+P334,P362,P370+P378,P402+P404,P501 | |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Otheranions | Sodium oxide Sodium sulfide Sodium selenide Sodium polonide |
Othercations | Hydrogen telluride Lithium telluride Potassium telluride Rubidium telluride Caesium telluride |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Sodium telluride is thechemical compound with theformula Na2Te. Thissalt is theconjugate base of the thermally unstableacidhydrogen telluride, but it is usually prepared by reduction oftellurium withsodium. Na2Te is a challenging material to handle because it is verysensitive to air. Air oxidizes it initially to polytellurides, which have the formula Na2Tex (x > 1), and ultimately Te metal. Samples of Na2Te, which are colourless when absolutely pure, generally appear purple or dark gray due to the effects of air oxidation.
The synthesis is typically conducted usingammonia as the solvent.[2]
Na2Te, like many related compounds with the formula M2X, adopts theantifluorite structure. Thus, in solid Na2Te each Te2− ion is surrounded by eight Na+ ions and each Na+ ion is surrounded by four Te2− ions.[3]
Simple salts of the type M2X, where X is a monatomic anion, are not typically soluble in any solvent because they have a highlattice energy. Upon addition of water - even moist air - or treatment with alcohols, Te2− protonates:
Because of this reaction, many processes attributed to Na2Te may involve NaHTe (CAS # 65312-92-7), which is more soluble and formed readily.
Na2Te finds use inorganic synthesis, both as areagent for reductions and as a source of Te in the synthesis oforganotellurium compounds.[4]Aryl halides are substituted to diaryl tellurides, as illustrated by the synthesis of dinaphthyltelluride:
Na2Te reacts with 1,3-diynes to give the corresponding tellurophene, which are structurally analogous tothiophenes:
As a reducing agent, Na2Te converts nitro groups to amines and will cleave certain C-X bonds.[4]
