CATALYSIS: THE GUIDE OF LIFE 



103 



torted or "activated" particle may combine with other particles, 

 or it may be split into smaller fragments. Catalysts thus function 

 like a duly qualified judge, who may wed or divorce couples who 

 come within his jurisdiction and remain there long enough for 

 the operation of due process of law. Another analogy is that the 

 catalyst functions like a "key" of a zipper closure. Drawn in one 



Figure 15. Dimensions of the nickel phthalocyanine molecule (/. M. Robertson). 

 (From paper in "Colloid Chemistry," Vol. 5, by J. Alexander, Reinhold Publishing 

 Corp., N. Y.) 



direction, the "key" massages the opposing "hooks" so that they 

 link together; if drawn in the opposite direction, the "key" 

 releases the bonded hooks from each other, and the closure opens. 

 The key and the hooks must be adjusted to each other within 

 rather close limits of size and shape. An adhering bit of solder or 

 paint, or a mechanical deformation of key or hooks may prevent 

 normal functioning, but a single key may open or close an enor- 

 mous number of bonds. 



