Metrohm 746 VA Trace Analyzer User Manual

Page 104

4.2 Lead determination with standard addition

746 VA Trace Analyzer / 747 VA Stand

4-19

standard addition

•

Remove stopper 25

25 and use a pipette to add 100

µµL lead ion standard

solution to the measuring vessel through the pipetting opening. Then

close the pipetting opening with stopper 25

25 and press the

key.

•

The sample solution spiked with standard addition solution is then

measured:

−

Purging and stirring for 30 s

−

Wait time 5 s to stabilize the analysis solution

−

Call-up of the segment

SegPb

three times for measured value

acquisition. The three individual measurements are given the VR

numbers

and

•

On completion of the 3

measurement of the sample solution, the pro-

gram is interrupted. The screen again shows the prompt to add 100

of the standard addition solution

PbStd

to the measuring vessel:

standard addition

•

Remove stopper 25

25 and use a pipette to add 100

µµL lead ion standard

solution to the measuring vessel through the pipetting opening. Then

close the pipetting opening with stopper 25

25 and press the

key.

•

The sample solution spiked with standard addition solution is then

measured:

−

Purging and stirring for 30 s

−

Wait time 5 s to stabilize the analysis solution

−

Call-up of the segment

SegPb

three times for measured value

acquisition. The three individual measurements are given the VR

numbers

and

•

On completion of the 3

measurement and calculation of the results, the

program is ended. The status display in the header of the "MONITO-

RING" dialog page switches back to

* READY *

, the instrument is ready

for a new determination.

Printout of reports and curves

•

On completion of the program, the reports and curves entered on the

"DOCUMENTATION" page are put out on the printer.

The printout of reports and curves can be stopped at any time by simultaneously
pressing the and keys.

ЪДДД

ДДД MEAS.TASK MESSAGE ДДДДДДДДДДДДДДДДДД

ДДДДДДДДДДДДДДДДДД¿

ADD PbStd 100.000 uL > M

press to break

АДДД

ДДД : continue ДДДДДДДДДДДДДДДДДД

ДДДДДДДДДДДДДДДДДДЩ