Hi 4015 silver/ sulfide half-cell – Hanna Instruments HI 4115 User Manual

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HI 4015 Silver/ Sulfide Half-cell

HI 4015 Silver/ Sulfide Half-cell
HI 4115 Silver/ Sulfide Combination

HI 4115 Silver/ Sulfide Combination

HI 4115 Silver/ Sulfide Combination
Electrode

Electrode

I. Introduction:

Introduction:

The Hanna HI 4015 and HI 4115 are ion selective elec-
trodes designed for the measurement of Silver/ Sulfide ions
in aqueous solutions. The HI 4015 is a solid state half-cell
sensor that requires a separate reference. The HI 4115 is a
combination ion selective electrode.

IIII

IIII.

Specifications

Type:

Solid State electrode with
a Silver/ Sulfide pellet.

Ion(s) measured:

Silver (Ag

), Sulfide (S

)

Measurement range: Silver

1.0 M to 1 X 10

-6

(107,900 to 0.11 ppm)

Sulfide 1.0 M to 1 X 10

-7

(32,100 to 0.003 ppm)

Interfering ions:

Mercury must be absent.
Ions that complex with
measured species will re-
duce measured ion con-
centrations.

Operating Temperature:

0-80

°C

Operating pH:

2-8 pH (For Silver)
12-14 pH (For Sulfide)

Dimensions:

12 mm (OD) X 120 mm
nominal insertion
(0.47

” X 4.72”)

Connection:

BNC

III.

III. Theory of Operation

Theory of Operation

Theory of Operation:::::

The HI 4015 or HI 4115 Silver/ Sulfide electrodes are po-
tentiometric devices used for the rapid determination of free
silver or sulfide ions. They can be used as an indicator
following the progress of a halide titration with silver ni-
trate. Sulfide ion determinations are made in ground wa-
ters, soils and paper liquors. The electrode functions as a
sensor or ionic conductor. The HI 4015 requires a separate
reference electrode to complete its electrolytic circuit. The HI
4115 has a double junction reference electrode incorpo-
rated in its design. The silver/ silver- sulfide pellet is prac-
tically insoluble in the test solutions being measured and
produces a potential change due to changes in the sample

’s

ion activity. When the ionic strength of the sample is fixed
by the addition of ISA, the voltage is proportional to the
concentration of silver or sulfide ions in solution and the
electrode follows the Nernst equation.

E= E

+ 2.3 RT/nF log A

ion

E= observed potential

= Reference and fixed internal voltages

R= gas constant (8.314 J/K Mol)

n= Charge on ion (2

for sulfide), (1+ for silver)

=ion activity in sample

T= absolute temperature in K

F= Faraday constant (9.648 x 10

C/mol)