eutech-instruments silversulfide epoxy Manuale Utente

Silver/Silver Sulfide Electrode 

 

Instruction Manual 

 

16

5. 

Add 1 ml of titrant and record the mV reading after stabilization. Repeat this operation 
four more times. 

 
6. 

Using Gran's Plot paper, plot the values as follows: 

 

a)  The horizontal axis is the volume axis. Each major division is equal to 1 ml of titrant 

used. 

 
b)  The vertical axis is the mV axis. Each major division is equal to 5 mV. The axis 

should be scaled so that the mV value obtained after 5 ml of titrant added is near the 
top of the graph. 

 
7. 

After drawing a straight line through the points, the line should intersect the horizontal axis 
at 0 ml.  (See Figure 4.) 

 
8. 

Measure out 100 ml of the sample into a 150 ml beaker, add 1 ml of low level ISA, place 
the beaker on the magnetic stirrer, and begin stirring. 

 

9. 

Prepare a 10 ml burette with the low level chloride titrant mentioned in Step 3 above. 

10.  Allow the titrant to run slowly into the sample until the mV reading is near the value 

recorded for the first 1 ml increment added in Step 5 above. Record the mV reading and 
the total volume added. 

 
11. 

Add 1 ml increments of titrant and record the mV reading vs the total volume until the mV 
reading approaches the highest mV reading recorded in Step 5 above. 

 
12. 

Plot the mV reading vs total volume for all points on the Gran's Plot paper. Draw a straight 
line through as many points as possible, extending the line to the horizontal axis. The 
volume intercept value is equal to the chloride concentration in ppm. 

 

 
A special method for measuring low level cyanide concentration. The silver/sulfide electrode is 
capable of cyanide measurements down to 0.03 ppm.