Instruction Manual
Iodide Electrode
1
EUTECH INSTRUMENTS PTE LTD.
INSTRUCTION MANUAL
IODIDE ION ELECTRODE
Page 1: ...Instruction Manual Iodide Electrode 1 EUTECH INSTRUMENTS PTE LTD INSTRUCTION MANUAL IODIDE ION ELECTRODE...
Page 2: ...ment 6 Direct Measurement of iodide using a pH mV meter 6 Direct Measurement of iodide using an ion meter 7 Low Level Iodide Determinations using a pH mV meter 8 ELECTRODE CHARACTERISTICS 8 Reproducib...
Page 3: ...his solution from your own laboratory stock half fill a 1 000 ml volumetric flask with distilled water and add 425 grams of reagent grade sodium nitrate Swirl the flask gently to dissolve the solid Fi...
Page 4: ...ord the mV reading 4 Determine the difference between the two readings The electrode is operating correctly if the mV potential has changed by a difference of 57 3 mV assuming the solution temperature...
Page 5: ...gh ionic strength prepare standards whose composition is similar to the sample Dilute concentrated samples 0 1M before measurement Use fresh standards for calibration Use 2 ml of ISA for each 100 ml o...
Page 6: ...re standards with a composition similar to the samples if the samples have an ionic strength above 0 1M 2 Place the most dilute solution 1 0X10 4 M or 10 ppm in a 150 ml beaker on the magnetic stirrer...
Page 7: ...ibration curve 7 The calibration should be checked every two hours Assuming no change in ambient temperature place the electrode tips in the mid range standard After the reading has stabilized compare...
Page 8: ...6 above The meter should be re calibrated daily Low Level Iodide Determinations using a pH mV meter For the iodide electrodes no special low level determination is necessary Linear response is possibl...
Page 9: ...t is the maximum level of iodide tolerable in a sample whose iodide concentration is 10 4M Using Table 2 the maximum ratio is Br 1 5X103 I 1 or Br 1 5X103 I 1 5X103 1X10 4 Br 1 5X10 1 M maximum bromid...
Page 10: ...mperature vs Values for the Electrode Slope Temp oC S 0 54 2 10 56 2 20 58 2 25 59 2 30 60 1 40 62 1 50 64 1 If changes in temperature occur the electrodes should be recalibrated The temperature range...
Page 11: ...mp cotton 8 Continue with Steps 3 and 4 above Limits of Detection The upper limit of detection in pure sodium iodide solutions is 1M In the presence of other ions the upper limit of detection is above...
Page 12: ...otential is described by the Nernst equation E Eo S log X where E measured electrode potential Eo measured potential a constant S electrode slope 57 mV decade X level of iodide ions in solution The ac...
Page 13: ...lity of hydrogen and hydroxide ions in samples make it impossible to mask their effect on the junction potential with any concentration of an equitransferent salt One must either calibrate the electro...
Page 14: ...o check the standard and reagent solutions If in doubt about the credibility of any of the solutions prepare them again Errors may result from contamination of the ISA incorrect dilution of standards...
Page 15: ...ing strap Readings readings continuously or air bubble on membrane remove bubble by re dipping electrode rapidly changing electrode exposed soak electrode in iodide standard to interferences defective...
Page 16: ...llivolts on the linear axis but calibration of semi log paper On the log axis be sure that curve is good concentration numbers within each decade are increasing with increasing concentration incorrect...
Page 17: ...lutions only avoid organic solvents Size 110 mm in length 12 mm in diameter 1 m cable length Storage Store in iodide solution ORDERING INFORMATION CODE NO DESCRIPTION EC IO 03 Iodide Ion Combination E...
