Spectroquant Pharo 300 - Page 280

114758
Test
Measuring 0.05 – 3.00 mg/l Cr 0.11 – 6.69 mg/l CrO
4
10-mm cell
range: 0.03 – 1.50 mg/l Cr 0.07 – 3.35 mg/l CrO
4
20-mm cell
0.010 – 0.600 mg/l Cr 0.02 – 1.34 mg/l CrO
4
50-mm cell
Expression of results also possible in mmol/l.
Shake the test tube vig-
orously to dissolve the
solid substance.
Quality assurance:
To check the measurement system (test reagents,
measurement device, and handling) ready-f
or-use
chromate standard solution Certipur
®
, Cat.No. 119780,
concentration 1000 mg/l CrO
4
2–
, can be used after diluting
accordingly.
Add 5.0 ml of the sample
with pipette and mix.
Place 1 level grey micro-
spoon of Cr-1 into a dry
test tube.
Add 6 drops of Cr-2.
Chromate
Determination of chromium(VI)
Transfer the solution into
a corresponding cell.
Select method with
AutoSelector.
Place the cell into the
cell compartment.
Important:
For the determination of total chromium = sum of
c
hromium(VI) and chromium(III) a pretreatment
with Crack Set 10C, Cat.No. 114688, or Crack Set 10,
Cat.No. 114687 and thermoreactor is necessary.
Result can be expressed as sum of chromium ( Cr).
To measure in the 50-mm cell, the sample volume and
the volume of the reagents have to be doubled for each.
Alternatively, the semi-microcell, Cat.No. 173502, can be
used.
Reaction time:
1 minute
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.
Release 06/2014 - Spectroquant
®
UV/VIS Spectrophotometer Pharo 300