THE USE OF LIQUID AMMONIA AS A SOLVENT 115 



interact in the same way that a dibasic acid and either one or 

 two molecules of a base interact : 



CH 3 .CO.NH.,+ KNH, = CH 3 . CO . NHK + NH 3 



The ammonia solutions of these substances— if the term 

 11 ammono-salt " is justifiable — should conduct electricity. 

 Measurements have only been made with one of them — mercury 

 succinimide — which was found to give a good conducting 

 solution. Besides the simple ammono-salts, there are others 

 analogous to the aluminates, plumbates and zincates. For 

 example, some of the ammonia derivatives of silver, copper, 

 aluminium and lead dissolve in excess of potassium amide 

 solution, just as many of the metallic hydroxides dissolve in 

 excess of caustic potash. Ammono-basic salts also exist and 

 are produced by the action of ammonia on the simple salts in 

 precisely the same way that ordinary basic salts are produced 

 by the hydrolytic action of water. The term " ammonolysis " is 

 suggested by Franklin for this kind of action, which resembles 

 hydrolysis in all its details. The formation of ammono-basic 

 salts by ammonolysis is reversible, the amount of precipitate 

 being increased by the addition of an ammono-base and 

 diminished by adding an ammono-acid. Examples are : 



HgCl 2 + 2NH a ^ NH,HgClppt. + NH 4 C1 

 2PbI, + 6NH 3 ^> Pb(NH s ) s PbNH 2 Ippt + 3NHJ 



The NH 2 is analogous to OH in ordinary basic salts and 

 the ammonium salt liberated is analogous to the acid liberated 

 by ordinary hydrolysis. 



Cf. Hg(N0 3 )2 + H,0 ^> HO . HgN0 3 + HNO ;j 

 BiCl 3 + 2H.0 j£ Bi(OH)Xl + 2HCI. 



Other Interactions in Liquid Ammonia 



The interactions of sodium or potassium amide and solutions 

 of metallic salts have already been mentioned but they are of 

 sufficient importance to be considered again in a little more 

 detail, as they throw much light upon the nature of many well- 

 known compounds. Mercuri-ammonium compounds are very 

 numerous, the most familiar being the " infusible white precipi- 

 tate " which is looked upon by various authorities as mercuri- 

 ammonium chloride : 



Hg= NHXl 



