@article { ISI:000370464800023,
	title = {Complexation key to a pH locked redox reaction},
	journal = {Journal of Chemical Education},
	volume = {93},
	number = {2},
	year = {2016},
	month = {FEB},
	pages = {355-361},
	publisher = {AMER CHEMICAL SOC},
	address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
	abstract = {<p>An unfavorable pH can block a feasible electron transfer for a pH dependent redox reaction. In this experiment, a series of potentiometric titrations demonstrate the sequential loss in feasibility of iron(II) dichromate redox reaction over a pH range of 0-4. The pH at which this reaction failed to occur was termed as a pH locked reaction. The comparative ability of 10 selected iron binding ligands with varied propensity for the redox potential modification of Fe(III)/Fe(II) redox couple to restore/unlock the pH locked redox reaction is shown using potentiometric titrations. The spectrophotometric speciation analysis of Fe(III) Tiron complexation with pH was carried out to explain the differing ability of EDTA and Tiron to unlock the reaction under different pH Conditions. The experiment illustrates how environmental, biological redox reactions avoid severe laboratory conditions to occur and can be explored in the design of novel redox systems for natural attenuation of environmental toxins to their non- or lesser-toxic forms. The experiment also demonstrates prudent laboratory practice for safe waste disposal.</p>},
	keywords = {Analytical Chemistry, Aqueous Solution Chemistry, Coordination Compounds, Oxidation/Reduction, pH, Physical Chemistry, Potentiometry, Second-Year Undergraduate, Thermodynamics, Titration/Volumetric Analysis, Upper-Division Undergraduate},
	issn = {0021-9584},
	doi = {10.1021/acs.jchemed.5b00499},
	author = {Rizvi, Masood Ahmad and Dangat, Yuvraj B. and Shams, Tahir and Khan, Khaliquz Zaman}
}
