7 standard addition technique – Metrohm 797 VA Computrace User Manual

Page 257

8.7 Standard addition technique

797 VA Computrace – Software

245

Start determination.

8.7

Standard addition technique

Use manual standard addition without solution exchange

In the manual standard addition without solution exchange, a
known amount of the analyte is added once or several times to the
sample using a pipette. Proceed as follows:

1. Click on

MAIN WINDOW

/ Mode / Determination

2. Click on

MAIN WINDOW

/ Window / Working method

specification

to open the

WORKING METHOD SPECIFICATIONS

window.

3. Load the desired method into the

WORKING METHOD SPECIFI-

CATIONS

window (see How to Load a method, section 8.4).

4. Select

Standard addition

in the

Calibration

field of the

WORK-

ING METHOD SPECIFICATIONS

window.

5. Select

Manual

in the

Addition

field of the

WORKING METHOD

SPECIFICATIONS

window.

6. Select

Batch

in the

Technique

field of the

WORKING METHOD

SPECIFICATIONS

window.

7. Click

to open the

EDIT WORKING METHOD PA-

RAMETERS

window.

8. Select

the

Determination

tab (see section 5.2) and enter

Sample

identifier

Sample amount

(not with the modes CVS and CPVS)

Cell volume

, and the number of standard additions in the

No. of

additions

field. (If you work with the CVS or CPVS mode, see

section 6.2 Calibration techniques with CVS and CPVS for a de-
scription of the parameters on the

Determination

tab).

9. Select

the

Substances

tab (see section 5.2) and make sure that

for each substance entered in the table the number of the sin-