eutech-instruments silversulfide epoxy Manuel D’Utilisation

Instruction Manual 

 

Silver/Silver Sulfide Electrode 

 

7

7. 

Read the electrode slope according the meter manufacturer's instructions. Correct electrode 
operation is indicated by a slope of 90-100%. See the 

 section if the 

slope is not within this range. 

 
 

 
All samples and standards should be at the same temperature for precise measurement. A difference 
of 1 

o

C in temperature will result in about a 2% measurement error. 

 
Constant, but not violent, stirring is necessary for accurate measurement. Magnetic stirrers can 
generate sufficient heat to change the solution temperature. To counteract this effect, place a piece 
of insulating material, such as styrofoam sheet, between the stirrer and beaker. 
 
All silver samples and silver standards should be stored away from light. 
 
Always dilute sulfide samples with SAOB (1:1) when they are collected. 
 
Always rinse the electrodes with distilled water and blot dry between measurements. Use a clean, 
dry tissue to prevent cross-contamination. 
 
A slow-responding electrode may point to deposits on the membrane. Use polishing paper to 
remove such deposits. See the section on 

. 

 
For low level silver measurements, use labware made of plastic. 
 
For samples with high ionic strength, prepare standards whose composition is similar to the sample. 
 
Always check to see that the membrane is free from air bubbles after immersion into the standard or 
sample. 
 

 
All samples must be aqueous and not contain organics which can dissolve the epoxy electrode body 
and/or cement bonding the sensing crystal to the electrode body. Infrequent measurements in 
solutions containing methanol, benzene, or acetone are permitted. Please check with Eutech 
Instruments Pte Ltd. before using the electrode in other organic solvents. 
 
The temperature of the standard solution and of the sample solution should be the same and below 
80oC. 
 
Samples containing sulfide must be buffered with SAOB to convert HS-

1

 and H

2

S to S

-2

. 

 
Samples containing silver must be below pH 8 to avoid reaction with OH

-1

. Silver samples should 

be acidified with 1M HNO

3

, if necessary.