284 Linhart — Hydrolysis of Alky I Metallic Sulphates. 



sion Krernann states that the reaction proceeds to a very 

 small degree according to the following equation : 



" Ba(0 2 H B SO 4 ) 2 + 4NaOH=BaS0 4 + Na 2 S0 4 + 2C 2 H 5 OH + 2H 2 0" 



and he considers it to be a reaction of the fifth order.* It is 

 evident that in place of the 2H 2 there should be 2NaOH or 



Ba(C 2 H 5 S0 4 ) 2 + 2NaOH = BaS0 4 + Na 2 S0 4 + 2C 2 H 5 OH, 



which is plainly a reaction of the third order. 



Theory. — When a solution of ethyl barium sulphate (one 

 mol per liter) is mixed with a solution of sodium hydroxide 

 free from C0 2 (two mols per liter) in equal volumes, barium 

 hydroxide is at once precipitated in crystalline form. This is 

 due to the fact that barium hydroxide is not soluble to that 

 extent at room temperature, especially in the presence of 

 sodium hydroxide. We may, therefore, assume that when 

 equal volumes of ethyl barium sulphate (0*6 gram equiva- 

 lents per liter) and sodium hydroxide (2*7 gram equivalents 

 per liter) are mixed, some of the ethyl barium sulphate is 

 changed to barium hydroxide according to : 



Ba(C 2 H & S0 4 ) 2 + 2NaOH<=^2NaC 2 H 6 S0 4 + Ba(OH) 2 



The probable reactions, therefore, taking place in the saponifi- 

 cation of the two esters by the two bases may be represented 

 by the following equations : 



(a) Ba(C 2 H 5 S0 4 ) 2 + NaOH = BaS0 4 + NaC 2 H 5 S0 4 + C 2 H 5 OH, 



(b) Ba(C 5 H 5 S0 4 ) 2 + Ba(OH) 2 = 2BaS0 4 + 2C 2 H 5 OH, 



(c) NaC,H B S0 4 + Ba(OH), = BaS0 4 + NaOH + C 2 H 5 OH, 



(d) NaC 2 H 5 S0 4 + NaOH = Na 2 S0 4 + C 2 H 5 OH ; 



the sodium sulphate immediately reacts with the ethyl barium 

 sulphate and barium hydroxide : 



Ba(C 2 H 5 S0 4 ) 2 + Na 2 S0 4 = BaS0 4 + 2NaC 2 H 5 S0 4 , and 

 Ba(OH) 2 + Na 2 S0 4 = BaS0 4 + 2XaOH. 



* " — Wiirde hingegen der Zerfall von atylschwefelsanrem Baryt haupt- 

 sachlich durch NaOH direkt erfolgen, ware diese Reaktion nach 



Ba(C2H 6 S0 4 ) 2 + 4NaOH = BaSO* + Na 2 S0 4 + 2C a H 6 OH + 2H a O (?) 



zu formulieren. Es wiirde also eine Reaktion fiinfter Ordnung resultieren. 

 Die Tatsache, dass der Reaktionsverlanf anfanglich annahernd durch eine 

 Gleichung ersterOrdnnngdarstellbar ist, spricht f iir die Unwarscheinlichkeit 

 der Annahme der Gleichnng 7. Naturlich soil nicht geleugnet werden, dags 

 zn gewissem, aber untergeordnetem Betrag die Reaktion des Zerfalles von 

 athylscnwefelsaurem Baryt anch n*ch Gleichnng 7 vonstatten gehen kann. 

 Hieranf wiirde sogar die Tatsache deuten, dass die anfangliche Reaktions- 

 geschwindigkeit mit steigender Konzentration des NaOH starker zunimmt 

 als der direkten Proportionalitat zwischen Reaktionsgeschwindigkeit nnd 

 Konzentration des NaOH entspricht." R. Krernann, Monatsh. fur Chem. 

 (3), xxxi, 175. 



