Chloride Titrations in Tap Water with Potentiometric end-point indication

Chloride Titrations in Tap Water with Potentiometric end-point indication

Equipment
Potentiometer = 751 GPD Titrino / Titroprocessor
Electrodes = 6.0430.100 Ag Titrode amalgamated; input 1

Reagents
c(AgNO3) = 0.01 mol/L; D0

Sample
100 mL tap water
0.5 mL c(HNO3) = 2 mol/L

Remarks
. Calculations:

Chloride=EP1*C01*C02*C03/C00;2;ppm

Chloride = fraction of chloride in ppm
C01 = concentration of titrating agent (0.01 mol/L)
C02 = molecular mass of Cl- (35.45 g/mol)
C03 = factor for ppm (1000)

. Answer

Chloride = 1.533 x 0.01 x 35.45 x 1000 / 100 = 5.43 ppm

EP1 = 1.533 mL
C00 = 100 mL

Literature

Metrohm Application Bulletin No. 130: Chloride titrations with
potentiometric end-point indication.

Method documentation

'pa
751 GPD Titrino 15215 751.0010
DET U Chloride
parameters
>titration parameters
meas.pt.density… 4
min.incr. …10.0 ml
dos.rate max…. ml/min
signal drift …50 mV/min
equilibr.time …26 s
start V:… OFF
pause …0 s
dos.element:… internal D0
meas.input: …1
temperature… 25.0 °C
>stop conditions
stop V: …abs.
stop V …99.99 ml
stop U …OFF mV
stop EP …1
filling rate max…. ml/min
>statistics
status: …OFF
>evaluation
EPC …5
EP recognition:… all
fix EP1 at U …OFF mV
pK/HNP: …OFF
>preselections
req.ident: …OFF
req.smpl size:… OFF
activate pulse: ….OFF
------------
'fm
751 GPD Titrino 15215 751.0010
DET U…. Chloride
>calculations
Chloride=EP1*C01*C02*C03/C00;2;ppm
C00= 100
C01= 0.01
C02= 35.45
C03= 1000
------------
'fr
751 GPD Titrino 15215 751.0010
U(init) 17 mV DET U Chloride
smpl size….. 100 ml
EP1… 1.533 ml… -38 mV
Chloride… 5.43 ppm
stop EP reached
============
'cu
751 GPD Titrino 15215 751.0010
start V 0.000 ml DET U Chloride
1.0 ml/div dU=20.0 mV/div
============