eutech-instruments iodide epoxy Manuel D’Utilisation

Instruction Manual 

 

Iodide Electrode

 

 

4

GENERAL PREPARATION 
 

 
Remove the rubber caps covering the electrode tips and the rubber insert covering the filling hole of 
the combination electrode or of the reference electrode. Fill the reference electrode or the 
combination electrode with the filling solution shipped with the electrode to a level just below the 
fill hole. No preparation is required with a sealed reference electrode. 
 
Connect the electrodes to the proper terminals as recommended by the meter manufacturer. 
 

(Check electrodes each day) 
 

1. 

To a 150 ml beaker, add 100 ml of distilled water and 2 ml of ISA. Place the beaker on a 
magnetic stirrer and begin stirring at a constant rate. After assuring that the meter is in the 
millivolt mode, lower the electrode tips into the solution. 

 
2. 

Using a pipet, add 1 ml of either the 0.1M or the 1,000 ppm standard to the beaker.  When 
the reading is stable, record the mV reading. 

 
3. 

Using a pipet, add 10 ml of the same standard used above to the beaker. When the reading 
has stabilized, record 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 is 25

o

C. See the 

TROUBLESHOOTING 

sections if the potential change is not 

within this range. 

 

Slope is defined as the change in potential observed when the concentration changes by a factor of 
10. 
 

(Check electrodes each day) 
 

1. 

Prepare standard iodide solutions whose concentrations vary by tenfold. Use either the 
0.1M or the 1,000 ppm iodide standard. Use the serial dilution method for this preparation. 

 
2. 

To a 150 ml beaker, add 100 ml of the lower value standard and 2 ml of ISA. Place the 
beaker on a magnetic stirrer and begin stirring at a constant rate. Lower the electrode tips 
into the solution. Assure that the meter is in the concentration mode. 

 
3. 

Adjust the meter to the concentration of the standard and fix the value in the memory 
according to the meter manufacturer's instructions. 

 
4. 

Rinse the electrodes with distilled water and blot dry. 

 
5. 

To another 150 ml beaker, add 100 ml of the higher value standard and 2 ml of ISA.  Place 
the beaker on a magnetic stirrer and begin stirring at a constant rate. Lower the electrode 
tips into the solution.