COLLATERAL READLXG 31 



The relation of adsorption to many of the processes and phenomena men- 

 tioned above will receive further attention in subsequent chapters of this book. 

 There are probablj- few if any processes occurring in living organisms in which 

 adsorption phenomena are not at least indirectly involved. Adsorption and 

 other interfacial phenomena are responsible for many of the so-called "vital" 

 activities of living cells. 



Discussion Questions 



1. Describe the appearance of liquid water at and near a water-air boundary 



were you able to observe the individual molecules. What changes would 

 result if the temperature were to rise 10° C? If alcohol were added to 

 the water? If sodium chloride were added to the water? 



2. List some of the interfaces which are present in a plant cell. 



3. Why aren't the nuclei of plant cells always spherical? 



4. Why do two clean drops of mercury join and form a larger drop when 



brought into contact? 



5. List some physiological processes which involve adsorption phenomena. 



6. How would you expect temperature to affect the rate of adsorption? The 



amount of adsorbate retained at equilibrium? 



7. What is the difference between adsorption and absorption? 



8. Olive oil released beneath pure water will rise to the surface as large spherical 



drops. When released beneath a i per cent solution of NaOH no drops 

 are formed, the oil rising to the surface as a thin stream. Explain. 



Suggested for Collateral Reading 



Bajdiss, W. M. Principles of general physiology. 4th Ed. Longmans, 



Green and Co. London. 1924. 

 Gortner, R. A. Outlines of biochemistry. 2nd Ed. John Wiley and Sons. 



New York. 1938. 

 Rideal, E. K. An introduction to surface chemistry. Cambridge Univ. Press. 



Cambridge. 1926. 

 Willows, R. S. and E. Hatschek. Surface tension and surface energy. 3rd 



Ed. P. Blakiston's Son and Co. Philadelphia. 1923. 



