18
19
Titration of Sulfide
A silver/sulfide electrode may be used as an indicator to
follow the progress of a sulfide titration with lead
perchlorate. The lead perchlorate should be 10 to 20
times greater in concentration than that of the sulfide
sample. The sample is first mixed with an equal volume
of SAOB. During the titration the sensor follows the
decrease in the sulfide concentration while small
additions of lead perchlorate titrant are added and react
with the sulfide ions. Permit sufficient time for solution
reaction and electrode equilibration. The largest mV
change for given increment is the endpoint.
XIII.
XIII.
XIII.
XIII.
XIII.pH
pH
pH
pH
pH
For Silver measurements:
HI 4115 and HI 4015 electrodes may be used in solutions
with pH values between 2 and 8. Samples that fall
beyond this range should be adjusted with acid (HNO
3
) or
base (NaOH).
For Sulfide measurements:
Sulfide measurements are made in the presence of SAOB;
HI 4015-00 which adjusts the pH between 12 and 14 pH.
XIV.
XIV.
XIV.
XIV.
XIV. Storage and Care of the HI 4015 and
Storage and Care of the HI 4015 and
Storage and Care of the HI 4015 and
Storage and Care of the HI 4015 and
Storage and Care of the HI 4015 and
HI 4115 sensors
HI 4115 sensors
HI 4115 sensors
HI 4115 sensors
HI 4115 sensors
The HI 4015 sensor can be stored in very dilute standards
(<10
-4
M) for short periods of time and should be stored
dry with the protective cap on when not in use.
The model HI 4115 combination electrode can be left in
dilute standards (<10
-4
M) for short time periods.
For long term storage, the electrode should be drained and
washed of salts with distilled or deionized water. Unscrew
the upper cap and move outer sleeve up cable. Wrap the
ceramic junction on the inner stem with Parafilm
®
or
other sealing wrap. Place the protective cap provided over
the sensor membrane. Store dry disassembled electrode in
storage box provided with electrode.
XV.
XV.
XV.
XV.
XV. Conversion tables
Conversion tables
Conversion tables
Conversion tables
Conversion tables
For Ag
For Ag
For Ag
For Ag
For Ag
+
+
+
+
+
Multiply by
Multiply by
Multiply by
Multiply by
Multiply by
Moles/L (M) to ppm (mg/L)
1.0787 x 10
5
ppm (mg/L) to M (moles/L)
9.27x 10
-6
For S
For S
For S
For S
For S
2-
2-
2-
2-
2-
Moles/L (M) to ppm (mg/L)
3.207 x 10
4
ppm (mg/L) to M (moles/L)
3.12 x 10
-5
