COLORIMETRY SPECTROPHOTOMETRY 1 29 



monochromator indicates the concentration of the solution. Instruments 

 are available which are used exclusively as flame photometers, or a gas- 

 burner attachment is used as a substitute for the usual energy source 

 in one of the regular spectrophotometers. Flame photometry is specific; 

 that is, it analyzes one metal even in the presence of others. It is also able 

 to detect very small quantities of a metallic ion (quantities in the general 

 range of milligrams per liter). 



SELECTED REFERENCES 



Clark, George L., ed., Encyclopedia of Spectroscopy. New York: 

 Reinhold Publishing Corporation, 1961. A complete reference work 

 with articles written by competent authorities. 



From the bibliography : 



Strobel, Howard A., Chemical Instrumentation. 



Willard, H. H., L. L. Merritt, Jr., and John A. Dean, Instrumental 

 Methods of Analysis. Almost one-third of this book is devoted to 

 various optical and photometric methods of analysis and the instru- 

 ments in common use. 



