Metrohm 794 Basic Titrino - Manual (Page 15)

2.4 Tutorial
794 Basic Titrino
11
2.4.2 Development of a method, titration of an acid
Selection of the mode
4 × • Press repeatedly until "DET" appears in the display. For a description of the DET mode see page 25. • Confirm "DET" with • Now select the measured quantity: Press repeatedly until "pH" appears again in
• Press repeatedly until "DET" appears in
the display. For a description of the DET mode see
page 25.
• Confirm "DET" with
• Now select the measured quantity: Press
the display.
Confirm the measured quantity "pH" with
.
You are now ready to titrate.
For the titration put a Exchange Unit with c(NaOH) = 0.1 mol/L on the Titrino and rinse
the tubing and the buret Tipp with . Fill the buret again with .
Plug a combined pH glass electrode into measuring input 1 (Ind I).
Pipette 2 mL c(HCl) = 0.1 mol/L into your titration vessel, dilute with ca. 20 mL dist. water.
Put a magnetic stirrer in the titration vessel and place buret tip and electrode in the probe,
see page 157 for their arrangement.
Start the stirrer and press
During the titration the first line of the display shows the current measured value and the
volume already dispensed:
As soon as the instrument has found an equivalence point, this is shown on the second
line:
Let the titration continue for a short while, e.g. until ca. pH 11.50. Now stop it with
.
The first line now shows the mode "DET pH" and the name of the chosen method (here
"********" because this method has not been saved under a own name until now). Of
interest is the second line, which shows the equivalence point found.
mode
mode DET
DET pH ********
DET: pH
DET pH ********
pH 3.02 0.351 ml
pH 7.64 2.083 ml
EP1
DET pH ********
EP1 2.083 ml pH 7.64