Calcium selenides

Beryllium sulfide, BeS beryllium selenide, BeSe beryllium telluride, BeTe beryllium polonide, BePo magnesium sulfide, MgS magnesium selenide, MgSe magnesium telluride, MgTe calcium sulfide, CaS (oldhamite) calcium selenide, CaSe calcium telluride, CaTe strontium sulfide, SrS strontium selenide, SrSe barium sulfide, BaS barium selenide, BaSe barium hydrosulfide, Ba(HS)2 barium hydrosulfide tetrahydrate, Ba(HS)2 H20. 

Ca12AI14033 12-CALCIUM 14-ALUMINIUM 33-OXIDE 445 CsSs CALCIUM SELENIDE 486... 

Ans. The elements in Group VI require two electrons to complete their octets, but calcium. Group II, must lose two elections to complete its octet. The first three elements in Group VI are oxygen, O sulfur, S and selenium, Se. The compounds are CaO, calcium oxide CaS, calcium sulfide and CaSe, calcium selenide. 

Guanajuatite, see Bismuth selenide Gypsum, see Calcium sulfate 2-water... 

Hydrogen cyanide Calcium cyanide Potassium cyanide Sodium cyanide Hydrogen fluoride as F Hydrogen peroxide Hydrogen selenide as Se Hydrogen sulphide Hydroquinone... 

Ammonium sulphide) Barium sulphide Calcium sulphide Chromium (II) sulphide Copper (II) sulphide Diantimony trisulphide Dibismuth trisulphide Dicaesium selenide Dicerium trisulphide Digold trisulphide Europium (II) sulphide Germanium (II) sulphide Iron disulphide Iron (II) sulphide Manganese (II) sulphide Mercury (II) sulphide Molybdenum (IV) sulphide... 

Caesium selenide, 4265 Calcium polysulfide, 3942 Calcium sulfide, 3941 Cerium trisulfide, 3967 Chromium(II) sulfide, 4245 Cobalt(II) sulfide, 4218 Copper iron(II) sulfide, 4269 Copper(II) sulfide, 4285 Europium(II) sulfide, 4293... 

According to the specific task, different materials are used for the windows. Typical materials are sapphire, calcium fluoride, zinc selenide, diamond, and normal quartz. The selection of the materials depends on the pressure and, for spectroscpic investigations, also on the wavelength corresponding to the bonds of the species to be analysed. 

Phenyl selenide, CeHg.SeH.1—This selenide may be obtained as follows (1) Selenium tetrachloride is allowed to react with benzene in the presence of aluminium chloride. (2) Magnesium phenyl bromide in ether solution is treated with finely divided selenium and the addition product treated with cold hydrochloric acid. The ether layer is then removed, the extracted solution treated with more ether and the extracts combined, then shaken with one equivalent of sodium hydroxide, calculated on the basis of the total amount of selenium used, and dissolved in water to make a 25 per cent, solution. The ether solution is then dried with calcium chloride, the ether removed and the residue distilled, diphenyl diselenide and diphenyl selenide, B.pt. 303° C., being obtained. The sodium hydroxide solution on acidification with a slight excess of concentrated hydrochloric acid, followed by three more extractions with ether, gives on removal of the solvent almost pure phenyl selenide, B.pt. 182° C. The product melts at 60° C., and is insoluble in water, but dissolves in alcohol mercuric chloride gives a white precipitate.2... 

Phenyl ethyl selenide, C6H5.Se.C2H5.3—Phenyl selenide (10 grams) is dissolved in one equivalent of sodium hydroxide in the minimum of water, 50 c.c. of absolute alcohol then added, followed by 20 grams of ethyl bromide. The mixture is heated under reflux for fifteen minutes, then diluted with four times its volume of cold water, extracted three times with ether, the extract washed with water, dried over calcium chloride and distilled. Rectification of the oil obtained gives a 72 per cent, yield of the required selenide, boiling at 214° to 216° C. Treatment with bromacetic acid converts the selenide into phenyl-selenoglycollic acid.4... 

Caesium selenide, 4259 Calcium polysulfide, 3936 Calcium sulfide, 3935 Cerium trisulfide, 3961 Chromium(II) sulfide, 4239 Cobalt(II) sulfide, 4212 Copper iron(II) sulfide, 4263 Copper(II) sulfide, 4279 Europium(II) sulfide, 4287 Germanium(II) sulfide, 4413 Gold(ni) sulfide, 0116... 

Inorganic pigments are found in the earth. Iron and lead oxides provide earth colors. Copper calcium silicate and cobalt stannate provide blues. The colors burnt sienna and burnt umber come from iron oxides. Green pigments come from chromic oxide, calcinated cobalt, and zinc and aluminum oxides. Red pigments come from cadmium sulfide, cadmium selenide, and barium sulfate. All these chemical compounds come from the earth. 

Ignition on contact with furfuryl alcohol powdered metals (e.g., magnesium iron) wood. Violent reaction with aluminum isopropoxide -f- heavy metal salts charcoal coal dimethylphenylphosphine hydrogen selenide lithium tetrahydroaluminate metals (e.g., potassium, sodium, lithium) metal oxides (e.g., cobalt oxide, iron oxide, lead oxide, lead hydroxide, manganese oxide, mercur oxide, nickel oxide) metal salts (e.g., calcium permanganate) methanol + phosphoric acid 4-methyl-2,4,6-triazatricyclo [5.2.2.0 ] undeca-8-ene-3,5-dione + potassium hydroxide a-phenylselenoketones phosphorus phosphorus (V) oxide tin(II) chloride unsaturated organic compounds. 

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