Method ID: HI0002EN
0.1N Hydrochloric Acid Titrant Concentration
Titrator Application Methods: General Methods - r. 2.3
Description:
Method for the standardization (titer determination)
of 0.1N Hydrochloric Acid (HCl) titrant solution
against standardized 0.1N Sodium Hydroxide
(NaOH) solution. The results are expressed in N
(eq/L).
Reference:
AOAC Official Methods of Analysis, Official Method
936.15
Electrode:
HI 1131B Combination pH Electrode
HI 7662-T Temperature Probe
Reagents:
HI 70463 0.1N Hydrochloric Acid solution (1 L)
HI 70456 0.1N Sodium Hydroxide solution (1 L)
HI 70436 Distilled Water (1 gal)
Accessories:
HI 70300L Storage Solution (500 mL)
HI 7071 Electrode Fill Solution (4*30 mL)
HI 7004L pH 4.01 Buffer Solution (500 mL)
HI 7007L pH 7.01 Buffer Solution (500 mL)
HI 7010L pH 10.01 Buffer Solution (500 mL)
HI 740036P 100-mL Plastic Beakers (10 pcs)
10-mL Class-A Volumetric Pipette
NOTE: A pH electrode calibration is not needed for
this method.
Procedure:
Connect the pH electrode and temperature probe
to the titrator.
Press “Select Method” from the main screen. Use
the arrow keys to highlight „HI0002EN 0.1N HCl
Titr. Conc.‟ and press “Select”.
Install a 25-mL burette filled with 0.1N
hydrochloric acid solution (HI 70463) on pump-
one and verify that no air bubbles are present in
the burette or tubing. If necessary prime until all
air has been removed completely.
Use a class-A volumetric pipette to transfer
exactly 10.00 mL of standardized 0.1N sodium
hydroxide solution (HI 70456) to a clean 100-mL
plastic beaker. Add distilled water to the 50-mL
mark on the beaker.
For the determination of the exact concentration of
sodium hydroxide, follow HI0001EN 0.1N Sodium
Hydroxide Titrant Concentration.
Place the beaker under the stirrer assembly and
immerse the pH electrode, temperature probe and
stirrer. Ensure that the reference junction of the
pH probe is 5-6 mm below the surface. If
necessary add extra distilled water.
Press “Start”. The titrator will start the analysis.
At the end of the titration, after detection of the
equivalence point, 'titration completed‟ will appear
with the titrant concentration. The result is
expressed in N (eq/L) of hydrochloric acid.
Remove the electrodes and stirrer from the
sample and rinse them thoroughly with distilled
water.
Record the result (titer concentration).
NOTE: For improved accuracy, repeat this
procedure a minimum of three times and calculate
the average value.
For methods utilizing 0.1N HCl titrant solution,
follow the steps below to enter the
titer/standardized value.
Select the method utilizing 0.1N HCl.
Select „Method Options‟ from the main screen.
Using the arrow keys, highlight „Titrant Conc.‟ and
press “Select”.
Use the numeric keypad to enter the standardized
(titer) value of the titrant then press „Accept‟.
Press „Escape‟ to exit the Method Options screen
and select „Save Method‟ option.
Method Parameters:
Name: 0.1N HCl Titr. Conc.
Method Revision: 2.3
Titration Type: Standard Titration
Analog Board: Analog 1
Stirrer Configuration: Stirrer 1
Pump Configuration:
Titrant Pump: Pump 1
Dosing Type: Dynamic
min Vol: 0.030 mL
max Vol: 0.500 mL
delta E: 6.000 mV
End Point Mode: pH 1EQ point, 1st Der.
Recognition Options:
Threshold: 500 mV/mL
Range: No
Filtered Derivatives: No
Pre-Titration Volume: 5.000 mL
Pre-Titration Stir Time: 0 sec
Measurement Mode: Signal Stability
delta E: 1.0 mV
delta t: 2.0 sec
t-min wait: 3 sec
t-max wait: 15 sec
Electrode Type: pH
Blank Option: No Blank
Calculations: Stdz. Titrant by Volume
Dilution Option: Disabled
Titrant Name: 0.1N HCl
Analyte Size: 10.000 mL
Analyte Entry: Fixed
Maximum Titrant Volume: 15.000 mL
Stirring Speed: 1400 rpm
Potential Range: -2000.0 to 2000.0 mV
Volume/Flow Rate: 25 mL/50 mL/min
Signal Averaging: 1 Reading