Since [PbT-]/[HT2-] is approximately 20 to 1, most of the NTA in solution is present
as the lead chelate. The molar concentration of PbT- is just slightly less than the 9.7 ´
10-5 mmols/mL total NTA present. The atomic weight of lead is 207, so the
concentration of lead in solution is approximately 20 mg/L. This reaction is pHdependent
such that the fraction of NTA chelated decreases with increasing pH.