500 DIVERS AND HAGA : DECOMPOSITION OF 



(1). 2Cu(H2NSO,), = N20 + H20 + H,S04 + CuS04 + 

 Cu(HoNS03)2 = Cu(H2NS05)2 + Cu(H2NS03)o. 

 Such an equation expresses much of what happens in the de- 

 composition of a hydroxyamidosiilphate at a lower temperature, 

 but even in this case, and much more in the decomposition of 

 a hydroximidosulphate by copper sulphate, where the tempera- 

 ture is higher, a third molecule decomposes in another way. 

 The result is that the free sulphuric acid shown in the above 

 equation gets neutralised, and the third molecule of hydroxyami- 

 dosulphuric acid yields neither sulphate nor amidosulphate, all 

 its sulphur being eliminated as dioxide, its nitrogen as nitrous 

 oxide, and its hydrogen as water thus reverting to sulphurous 

 and hyponitrous acids, just as it does under the influence of an 

 alkali (p 497) adding to equation (I) that of Cu(HoNSOj),=N,0+ 

 2H,0 + 2SO. + CuO, we get (2), 3Cu(H,NSOJo=2N.>0 + 4H,0 + 

 2S02+2CuSO, + Cu(tLNSO,)„ with products free from acid. 



It is possible to express the decomposition of hydroxy- 

 amidosulphate differently, by making nitrogen one of the pro- 

 ducts in place of nitrous oxide, thus : 



(3)3Cu(H2NSOJ.>=2No + 2HoO + 2HoSO,+ 2CuSO,+ Cu(H,^'S03),; 

 (4) Cu(H2NS04).2 = K + 2H2O + SO2 + CUSO4. 



In (3) sulphur dioxide is not a product whilst in (4) it is. 

 AVhether, however, nitrogen is formed, even in small quantity, 

 is doubtful. Along with the nitrous oxide soluble in alcohol, we 

 found a little insoluble gas— about 4 per cent, by volume of the 

 wiiole gas, — but we are not prepared to assert that this was not 

 due to air in spite of the precautions we took to expel all air 

 from the apparatus by carbon dioxide before the decomposition. 

 It will be seen from the equations that, with nitrous oxide as a 

 product of the decomposition, the sulphur appearing as sulphate 



