Spectrophotometric Analysis 



59 



-0.01 



- 0.02 



- 0.03 



- 0.04 



0.05 

 0.06 



0.07 ** 



- 0.08 = 

 o 



0.09 1- 



0.10 - 



E 



0.15 w 



- 0.20 



- 0.30 



0.40 

 0.50 

 0.60 



0.70 



0.80 



0.90 



1.00 

 420 440 460 480 500 520 540 560 580 600 620 640 660 680 700 



Wave Lengths in Millimicrons 



Fig. 4. Absorption curves of five dyes of different colors: 



1. Tartrazine (yellow) 



2. Orange G. 



3. Fuchsin (red) 



4. Crystal violet 



5. Neptune blue BG. 



accepted as evidence of the presence of a second dye unless it has 

 been ascertained that it is not found with a pure sample of the dye 

 under conditions of examination. 



The absorption curve of a green dye is recorded in Fig. 5. It has 



