CHEMICAL PROPERTIES 



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factor determining these properties. Some properties of these acids and 

 their anions are compared in Table 2-1 for reference. The solubilities and 

 ionization constants are particularly different and provide much useful 

 information on the structure of the maleate ion. It is noteworthy that 

 maleate usually chelates more strongly than fumarate with cations, this 

 presumably being related to the closer intercarboxylate distance in maleate, 

 which is not much greater than for malonate (3.28 A). This complexing 

 with cations must always be considered in using maleate as an inhibitor, 

 especially at higher concentrations, since this alone may alter enzyme 

 activity or tissue function. 



Table 2-1 



Comparison of the Properties of Maleic and Fumaric Acids 



