ACIDITY 175 



7. What is a buffer? Write equations to illustrate the reaction of a buffer with 

 HCI and XaOH, respectively. 



8. What do pH 5, 7, and 9 mean with respect to acidity, neutrality, and alkalinity? 



9. How much more acid is the first member of the following pairs than the second 

 member: pH 6 vs. 7, pH 4 vs. 7, pH 4.2 vs. 6.3, pH 4 vs. 8.3, pH 2 vs. 10? 



10. Give the approximate pH values of six representative biological materials. 



11. Give the names and structural formulas of ten organic acids (other than fatty 

 acids) and five organic bases commonlj' found in biological materials. 



REFERENCES AND SUGGESTED READINGS 



Bonner, James, Plant Biochemistry, Academic Press, Inc., New York, 1950. 



Clark, W. M., The Dctermiimtioi of Hydrogen Ions, 3rd ed.. The Williams and 

 Wilkins Company, Baltimore, 1928. 



Kolthoff, I. M. and Laitinen, H. A., pH and Electrotitratiovs, 2nd ed., John Wiley 

 and Sons, Inc., New York, 1941. 



La Motte, F. L., Kenny, W. R., and Reed, A. B., pH a)td Its Practical Application, 

 The Williams and Wilkins Company, Baltimore, 1932. 



Pierce, W. C. and Haenisch, E. L., Quantitative Analysis, 3rd ed., John Wiley antl 

 Sons, Inc., New York, 1948. 



Schmidt, C. L. A. and Allen, F. W., Fundamentals of Biochemistry, 1st ed., McGraw- 

 Hill Book Company, Inc., New York, 1938. 



