440 CHEMISTRY OF THE LEUOOMAINS. 



hypobromate sets free about one-third of its nitrogen. The salts 

 of arginin have been especially studied by Gulewitsch.' 



The neutral chlorid, CgHj.Np^.HCl + Hp, is easily soluble in 

 water from which it can be crystallized on concentration or on addi- 

 tion of alcohol or ether. It is less soluble in hot than in cold 

 85 per cent, alcohol. It forms rosette-like masses of plates. The 

 water of crystallization may be driven off at 100° (Hedin). More- 

 over, the chlorid may crystallize from water without taking up water 

 of crystallization (Schulze^). Lawrow obtained a chlorid containing 

 one-half molecule of water. The anhydrous salt sinters at 208°, 

 gives off gas and melts at 209° or higher. When heated with 

 concentrated hydrochloric acid ammonia is split off, but only at high 

 temperatures — 180°- 200°. It is strongly dextro-rotatory; the 

 rotation is increased by acid and decreased by alkali. Hedin* was 

 unable to obtain a crystalline acid chlorid. 



The neutral nitrate, CgHj^N^^ .HNO3 + ^H^O, results on decom- 

 position of the basic silver or copper nitrate salts. It can be read- 

 ily crystallized from water or from hot dilute alcohol, forming 

 opaque chalk-like masses composed ot microscopic needles which tend 

 to effloresce. The salt is somewhat hygroscopic ; when dry it melts 

 imperfectly at about 175°. At 15° it is soluble in about two parts 

 of water. It is very easily soluble in hot, difficultly in cold 85 

 per cent, alcohol. The salt is dextro-rotatory and the rotation is 

 markedly affected by the presence of free acid. It dissolves copper 

 hydrate, forming the double salt. 



The neutral nitrate of the inactive arginin which Kutscher iso- 

 lated from antipepton (pp. 424, 439) forms small, glistening, trans- 

 parent four-sided prisms or plates, which often unite in groups and 

 do not contain water of crystallization. It is more difficultly soluble 

 than the dextro-salt (1 to 17.25 water at 20°; 1 to 21.7 parts of 

 water at 12°).* It sinters at 206° and melts at 211° with gas 

 formation. 



The acid nitrate, CgHj^Np,.2HN03 , is prepared by evaporating 

 the former salt with excess of acid. It forms long colorless needles 

 or masses of extremely thin elongated plates. The melting point is 

 144.5-145°. 



The sulphate, CjHj^N^j.HjSO^ , can be obtained by decomposing 

 the copper sulphate compound. It separates from saturated alco- 

 holic solution as an oil and has not been crystallized (G.). Hedin 

 also was unsuccessful in crystallizing the sulphate. It is hygro- 

 scopic and behaves to polarized light the same as the preceding salts. 



^Zeita. physiol. Chem., 27, 178. 

 " ZeUs. physiol. Chem., 29, 331. 

 ' Zeitx. phygml. Chem., 22, 157. 

 *Zeits. phygioU Chem., 32, 478. 



