Chemistry and Physics. 163 



In preparing the compound that has been described the authors 

 obtained a second substance which they had not yet been able to 

 purify. They are convinced, however, that it is mono-ethylated 

 hydrogen peroxide, C 2 H 5 H0 2 . This substance is miscible with 

 water, has an odor similar to chloride of lime, does not act upon 

 acidified permanganate or dichromate solutions, but behaves like 

 hydrogen peroxide with potassium iodide solution. — Berichte, 

 xxxiii, 3387. h. l. w. 



2. Ammonium Amalgam. — It has been recently shown by 

 Alfred Coehn that this well known, curious substance, which 

 swells up and gives off ammonia and hydrogen gases, is in all 

 probability what its name implies. It was found that at about 

 0° the ammonium amalgam produced by electrolysis is compara- 

 tively stable, does not swell up, and presents a perfectly metallic 

 appearance. When the amalgam under these conditions was 

 allowed to act upon a cooled copper sulphate solution, the for- 

 mation of metallic copper was readily seen, exactly as when potas- 

 sium amalgam is used. It was possible also to reduce cadmium 

 and even zinc from solutions of their sulphates by means of this 

 amalgam. No such striking evidence of the fact that ammonium 

 behaves like an alkali metal has been previously obtained, as sim- 

 ilar experiments have failed at higher temperatures. — Zeitschr. 

 anorg. Chem., xxv, 430. h. l. w. 



3. Hydrogen Telluride. — This gas which was discovered by 

 Davy in 1810, has not heretofore been prepared in a pure condi- 

 tion, although its composition, corresponding to the formula 

 TeH 2 , had been established by indirect means. Ernyei has 

 recently succeeded in preparing the pure substance. He first 

 obtained the gas mixed with only a small quantity of hydrogen 

 by means of electrolysis carried out at a temperature of —15 to 

 — 20°, using tellurium as a negative electrode in 50 per cent sul- 

 phuric acid with a current of 220 volts. By cooling the impure 

 product with solid carbonic acid the hydrogen telluride solidified 

 to lemon yellow needle-like crystals which melted at about —54° 

 to a greenish-yellow liquid. Hydrogen telluride is a colorless gas 

 possessing a very disagreeable odor and poisonous properties. 

 In contact with air it decomposes at once, and even below 0° in a 

 sealed tube it decomposes spontaneously into hydrogen and tellu- 

 rium in a few days. It burns with a bright, blue flame, and is 

 rather soluble in water. When passed into alkaline solutions it 

 forms tellurides, but in solution of salts none are formed. The 

 last statement corrects a generally accepted error. The vapor 

 density of the pure substance determined by the method of 

 Dumas gave the numbers 65-48 and 64*'72 compared with hydro- 

 gen as unity, while theory requires 64*8. In making these deter- 

 minations it was found that the liquid evaporated very slowly at 

 0°, but at 2 or 3° it went faster, The boiling point, therefore, is 

 probably a little above 0°. — Zeitschr. anorg. Chem., xxv, 311. 



h. l. w. 



