8 7 6 5 



-log (EDTA)^ (M) 



Figure 4-2. The effect of EDTA on the speciation of metals 



in Aquil. 



Note: Total metal concentrations are given in Table 4-1, with Pb, Cd, Hg, Ni, 

 Co, and Cr added as contaminants (10""M). A) The percent of each metal that 

 is chelated (MeEDTA) versus total EDTA concentration, (M); B) Metal ion 

 activity (M) versus total EDTA concentration (M). 



45 



