372 HEIXRICH ROSE ON ^ETHERIFICATION. 



a base, also causes the same decomposition. Some compound! 

 of the oxide of aethyl are as easily decomposed by water as bj 

 many bases ; so, for instance, is oxalic aether, which is convertec 

 by water into hydrate of oxalic acid and alcohol. A high tem- 

 perature is not even requisite to produce this change; for il 

 takes place at the common temperature, and indeed in a ver) 

 short time. 



But the acid sulphate of the oxide of aethyl, — or, rather 

 the combination of the sulphate of the oxide of aethyl, with 

 hydrated sulphuric acid (sulphovinic acid), also undergoes ir 

 its solution in water quite a similar decomposition. Even at tht 

 usual temperature alcohol and the hydrate of sulphuric acid 

 are gradually formed ; it proceeds more rapidly by boiling. This 

 process may likewise be most easily explained by the supposition 

 that water acting as a base eliminates the oxide of aethyl from 

 its combination with sulphuric acid, which, at the moment ol 

 its expulsion, takes up water and forms alcohol. 



The sohitions of nearly all sulphovinates in water are de- 

 composed, especially on boiling, in a similar manner. Alcoho. 

 and water evaporate, and a so-called acid sulphate, i. e. a double 

 compound of the neutral salt, which already pre-existed in tht 

 sulphovinate salt with the hydrate of sulphmic acid, is formed 

 in the solution. 



If sulphovinic acid is heated with merely a small quantity oj 

 water, no alcohol is obtained, but chiefly hydrated sulphuric 

 acid, and pure oxide of a;thyl or a2ther : — there is not sufficient 

 water present to convert the liberated aether into alcohol. 



If alcohol is mixed with the hydrate of sulphuric acid, sulpho- 

 vinic acid is formed, or a double compound of the neutral sul- 

 phate of the oxide of aethyl with the hydrated sulphuric acid. 

 By the formation of the sulphate of the oxide of cethyl two atoms 

 of water are set free, one from the hydrated sulphuric acid, the 

 other fi-om the alcohol. On heating the mixture, one of these 

 liberated atoms of water eliminates oxide of aethyl from its com- 

 bination with sulphuric acid, and combines with the acid, form- 

 ing the hydrate of sulphuric acid. 



But why does not the aether at the moment of its expulsion 

 combine with water and form alcohol ? There is sufficient 

 water present, for only one atom of water is requisite to expel 

 the jether ; and at the formation of sulpho\anic acid, even when 

 anhydi'ous alcohol is employed, two atoms are set free. 



