400 



500 600 



Wavelength in nnp 



700 



800 



Fig. 3.11. The variation of the temperature coefficient (Qgo) of the 

 bleaching rate with wavelength. (A) Results are compared with the 

 temperature coefficient of the extinction of visual purple (lower curve) 

 and also with a function calculated from the Arrhenius equation, 

 assuming that a total activation energy of 47,000 calories per gm mol is 

 required. (B) The two straight lines drawn through the results show 

 that the bleaching rate becomes temperature-dependent at about 590 m/z. 

 (5/. George, 1952) 



