HIRANUMA APPLICATION DATA

Factorstandardization

Data No.

Automatic Titrator

O4Feb. 03,
2022

Standardization of silver nitrate titrant

1. Abstract
The measurement method of chloride ions or salt content by precipitation titration using a silver nitrate
standard solution is widely used in the titration analysis. Factors are indicated on the commercially available
standard solution for volumetric analysis. The factor determination is required when the standard solutions areprepared in the laboratory. Also it is effective to check the repeatability by the factor measurement using astandard material to check the performance of titrator system. Japanese Industrial Standard JIS K 8001 and theJapanese Pharmacopoeia describe that sodium chloride, which is a standard material for a volumetric analysis,should be used for the factor determination of silver nitrate standard solution.
In this report, sodium chloride, which is a standard material, was dissolved in pure water, andpotentiometric titration was performed with 0.1 mol/L silver nitrate standard solution to determine the factor. 1
mol of sodium chloride and 1 mol of silver nitrate react quantitatively according to Eq. (1), and the titration
curve shows an inflection point at the end point.
NaCl ＋ AgNO3 → AgCl↓ ＋ NaNO3･･･(1)1) Japanese Pharmacopoeia Eighteenth Edition
2) Japanese Industrial Standard JIS K8001 General rules for test methods of reagents

2. Configuration of instruments and reagents(1) Configuration of instruments
Main unit: Automatic Titrator

COM SeriesElectrodes: Silver-reference combination electrode

AGR-811Z** It can also be applied to combinations of other silver electrodes such as AG-311
and silver comparison electrodes such as RE-241Z.
(2) Reagents
Titrant: 0.1 mol/L (0.1 N) silver nitrate standard solution (Buret No. 1)

Standard material : Sodium chloride, standard material for volumetric analysis(Certified value of purity in this report: 100.00 %)3. Measurement procedure(1) Take about 0.1 g of sodium chloride into a 100 mL beaker and weigh it accurately to 0.1 mg digits.
(2) Add 50 mL of DI water and a stirrer bar to the 100 mL beaker.
(3) Immerse the electrodes and start the measurement. Titration is performed with a 0.1 mol/L silver
nitrate standard solution, and the inflection point on the titration curve is detected as the end point.
(4) Perform the blank test with the same procedure of sample measurement.

4. Measurement conditions and results
Examples of titration conditions
Blank measurement

Cndt No.
1Method
AutoConstantNo.
1Mode No.
16 *1
Buret No.
1Size0 g
Pre Int
0 sec
Amp No.
2Blank0 mL
Del K
0D. UnitmV
Molarity
0.1 mol/L
Del Sens
0 mV
S-Timer
60 secFactor0Int Time
3 sec
C.P. mL
0 mL
K0Int Sens
3 mV
T Timer
0 sec
L0Brt Speed2D.P. mL
0 mL
Pulse
16End Sens
300
UnitmLOver mL
0.5 mL
FormulaD
Max.Vol.
1 mL
Digits3*1: Since the maximum change in electrode potential is shown at the first drop of this blank titration, the end
point is detected in the first drop or less volume. To detect this end point, set Mode No. to which the blankmode function is assigned, Mode No.12-19 for COM-A19.
Factor standardization measurement with sodium chloride

Cndt No.
MethodBuret No.
Amp No.
D. Unit
S-Timer
C.P. mLT Timer
D.P. mLEnd Sens
Over mLMax.Vol.

2Auto
12mV
60
001.0300
0.520secmL
secmL

ConstantNo.
SizeBlank
Molarity
FactorKL

200.010.1
1.000058.440gmLmol/L*2*3Mode No.
Pre Int
Del K
Del Sens
Int Time
Int Sens
Brt Speed
Pulse

409033240sec
mV
sec
mV

Unit
Fact2
mL
FormulamL
S*F*1000/(K*M*(D-B))
Digits
4*2: Purity of sodium chloride / 100*3: It is the mass (g) of sodium chloride that reacts with 1 mol of silver nitrate by the reaction formula (1),which is 58.44 of the formula amount of sodium chloride.

Measurement results
Measurement results of factor standardization
SampleBlank
Sodiumchloride

Measurement
No.
12123

Blank measurement

Samplesize (g)0.10280.10500.1082

Titrant
volume (mL)
0.010
0.010
17.67818.07618.605

Factor
0.9956
0.99450.9957

Statistical results
Avg.

0.01 mL

Avg.
SDRSD

0.995
0.001
0.07 %

Factor standardization measurement

Examples of titration curves

5. Note(1) About the standard material
Sodium chloride is used for the standardization of silver nitrate standard solution in precipitation titration.
The standard material for volumetric analysis comes with a certificate value of the purity and uncertainty. If
these certification and traceability are required for the management of test result, such as quality records, thestandard material for volumetric analysis is used. It is necessary to prepare the standard material withpretreatment such as drying as described in its instructions before use.
Keywords：Factor standardization, Precipitation titration, Silver nitrate, Sodium chloride