Appendix 



Glossary 



Ahiogenesis. The production of living matter 

 from non-living matter. 



Absolute Temperatures. Temperatures measured 

 from absolute zero. (Absolute zero is reached at —273° 

 centigrade, at which point the molecules are motion- 

 less.) 



Acids. Acids change the color of certain indi- 

 cators, dissolve metals, combine with bases, neutral- 

 ize alkalis, etc. Acids are defined as compounds 

 that in aqueous solution suffer electrolytic dissocia- 

 tion with formation of hydrogen ions. Some acids 

 are highly ionizable; many acids are not highly 

 ionized in ordinary solutions. A very extensive 

 literature treats of hydrogen ions. The accumulation 

 of data is so great that. Dr. Leonor Michaelis says, 

 no one person can master the entire field. See Elec- 

 trolytic Dissociation and Metal. 



Adsorption. The action of a substance in con- 

 densing and holding another substance by surface 

 condensation (as of colloids in taking up dissolved 

 substances). 



Analysis {Chemical). The determination and (or) 

 estimation of the constituents of a compound or 

 mixture is termed chemical analysis. There are 

 several branches of chemical analysis: (1) Qualita- 

 tive analysis, the process of detecting what elements 

 are present in a compound or mixture. (2) Quantita- 



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