Ion concentration
Multi 9430
64
ba75966e04
04/2015
6.3.4
Sample subtraction
With the "Sample subtraction" procedure, a known amount of sample is added
to the standard solution (complexing agent or precipitating agent).
The ion concentration in the sample is calculated from the change in potential.
The sample subtraction is one method for the indirect determination of ions. It
is used for the determination of ions for which no direct determination is possi-
ble.
Calibration
1.
Select the measuring method (see section 6.3 S
2.
If necessary, set the ion type for the ion in the standard (
Ion type
) with
<
> <
>
and
<ENTER>
.
On selection of the ion type that can be defined (ION):
Using
<
> <
>
and
<ENTER>
, set the valence (
Valency
) and molar
weight (
Molar mass
) for the ion in the standard solution.
3.
Select
continue
with
<
> <
>
and confirm with
<ENTER>
.
Ion type
S
continue
Sample subtraction
01.08.2013 08:00
4.
Prepare two standard calibration solutions.
5.
Perform a two-point calibration according to user guidance.
6.
The calibration record is displayed as soon as a stable value is
achieved for the second standard calibration solution.
01.08.2013 08:00
01.08.2013 08:00
#1 0.010 mg/l
374.4 mV 25.0 °C
#2 0.020 mg/l
358.1 mV 25.0 °C
Slp.: 54.1 mV
++ (Ion type: S)
CALIBRATION
ADA 94/IDS DIN
B092500013