Kinetic spectrophotometric method for the determination of trace amounts of oxalate by an activation effect.
A new, simple and inexpensive kinetic catalytic spectrophotometric method for the determination of oxalate is described. The method is based on an activation effect of oxalate on a catalytic effect of iron(II) on the oxidation of iodide by bromate. The reaction is monitored by measuring the absorbance of triiodide ion at lambda max = 352 nm. A calibration graph was obtained from 0.10 - 7.0 microg cm(-3) of oxalate with a detection limit of 0.080 microg cm(-3). The standard deviations for ten replicate determinations of 0.50, 1.0 and 5.0 microg cm(-3) of oxalate were 4.0, 2.6 and 1.8%, respectively. The applicability of the method was demonstrated by the determination of oxalate ion in real samples.
Chamjangali
Mansour Arab
MA
College of Chemistry, Shahrood University of Technology, Shahrood 36155-316, Iran. marab@shahrood.ac.ir
Keley
Vahid
V
Bagherian
Ghadamali
G
D001959:Bromates / Q000737:chemistry; D002384:Catalysis; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D007454:Iodides / Q000737:chemistry; D007477:Ions; D007501:Iron / Q000737:chemistry; D007700:Kinetics; D008956:Models, Chemical; D010070:Oxalates / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D015203:Reproducibility of Results; D013053:Spectrophotometry / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet; D014131:Trace Elements / Q000032:analysis*; D014867:Water / Q000737:chemistry
D001959:Bromates; D007454:Iodides; D007477:Ions; D010070:Oxalates; D014131:Trace Elements; D014867:Water; D007501:Iron; D010100:Oxygen