User Guide

17
6. Immerse the probe tip into the sample,
make sure the platinum electrodes are
submerged.
7. Adjust the potentiometric setting, us-
ing the “ ” and “ ” keys on the front
panel until the display reads about 1.00.
8. Dispense the titrant into the beaker in
small increments. Note the downward
reading on the amperometric titrator.
Record the display reading that corre-
sponds exactly to the mL of titrant
added. Record at least 3 points before
and 3 points after the End Point.
10.Construct a titration graph using the
PL 101 graph-paper.
11.Draw the best-fit line through each set of points. The End
Point is determined by the intersection of the two best lines
through the points.
12. Read directly the total chlorine concentration on the top
of the graph by drawing a straight vertical line through the
End Point or read the volume of titrant used until the End
Point and multiply by 2 when titrant (a) 0.00564N PAO is
used or multiply by 0.2 when titrant (b) 0.000564N PAO
is used.
mL
(till End Point)
x 2
(or 0.2)
= mg/L Total Cl
2
.