Release 08/2014 - Spectroquant
®
Multy
114552
Cell Test
Chromate
Determination of total chromium
= sum of chromium(VI) and chromium(III)
Quality assurance:
To check the measurement system (test reagents, meas-
urement device, and handling) ready-for-use chromate
standard solution Certipur
®
, Cat.No. 119780, concen-
tration 1000 mg/l CrO
4
2–
, can be used after diluting
accordingly.
Pipette 10 ml of the
sample into an empty
16-mm cell.
Measuring range: 0.05 – 2.00 mg/l Cr
16-mm cell
0.11 – 4.46 mg/l CrO
4
16-mm cell
Fill approx. 10 ml of
distilled water into an
empty 16-mm cell (do
not add any reagents!),
close with the screw
cap.
(Blank cell)
Select method 1 5 0 .
Insert the cell containing
the sample into the cell
compartment. Align the
mark on the cell with
that on the photometer.
Press Test .
Reaction time:
1 minute
Press Enter to start
the countdown.
Check the pH of the
sample, specified range:
pH 1 – 9.
If required, add dilute
sodium hydroxide
solution or sulfuric acid
drop by drop to adjust
the pH.
Add 6 drops of Cr-3K
into a reaction cell,
close with the screw cap.
Shake the cell vigorous-
ly to dissolve the solid
substance and leave to
stand for 1 minute.
Add 5.0 ml of the pre-
treated sample with
pipette, close with the
screw cap, and mix.
Add 1 drop of Cr-1K,
close with the screw cap,
and mix.
Add 1 dose of Cr-2K
using the blue dose-
metering cap, close the
reaction cell with the
screw cap.
Heat the cell in the
thermoreactor at 120 °C
(100 °C) for 1 hour.
Remove the cell from
the thermoreactor and
place in a test-tube rack
to cool to room tempera-
ture: pretreated sample.
Insert the blank cell into
the cell compartment.
Press Zero .
