In Table 4 the rate of destruction, that is, the velocity-coefficient k 2 

 multiplied by 1,000, is recorded for various strengths of hydrochloric 

 acid and sodium hydroxid solutions at 30 C. ; the results are also 

 shown in figure 2. 



TABLE 4. Rate of destruction of invertase at 30 C. by acid and alkali. 



SUMMARY. 



Acids and alkalis are found to affect the purified enzym invertase 

 in two ways; in small concentrations they influence its activity but 



Q.OG O.Q5 O.O4 O.O3 O.O2 O.O/ O O.O/ 0.<?<? 



o.os o.oe 



Fir;. 2. The rate of destruction of invertase at 30 C. by acid and alkali. 



do not permanently destroy it, in larger concentrations they accom- 

 plish its destruction. The destruction by acid at 30 C. reaches a 

 barely noticeable rate at 0.01 normal acidity and increases rapidly 

 with the acidit}^ until it becomes almost instantaneous at 0.05 normal. 

 The rate of destruction follows the formula for unimolecular reac- 

 tions. The alkaline destruction begins a little below 0.01 normal and 

 is almost instantaneous at 0.045 normal. The rates of destruction 

 are show r n in figure 2. 



[Cir. 55] 



