1911-12.] Preparation and Properties of Basic Copper Nitrate. 11 
3. The only basic nitrate of copper appears to be 
Cu(N0 3 ) 2 • 3Cu(OH) 2 . 
The product obtained by heating the trihydrate to 100° has this composi- 
tion, and is not Cu(N0 3 ) 2 * 2Cu(OH) 2 , as stated by Graham. 
4. Dehydration of copper nitrate does not yield anhydrous copper 
nitrate, but results in decomposition, with formation of basic copper nitrate, 
whether the dehydration is performed at ordinary or higher temperatures. 
5. Copper oxide does not interact with nitric anhydride. 
6. The only hydrates of copper nitrate appear to be the trihydrate and 
hexahydrate. The transition temperature is 24*65° (±0*05) corr. 
7. Concentrated nitric acid dehydrates the hexahydrate, while dilute 
nitric acid hydrates the trihydrate. It was not found possible to determine 
the concentration of nitric acid, which would be in equilibrium with both 
hydrates. 
Chemistry Department, 
University of Edinburgh. 
( Issued separately January 10 , 1912 .) 
