LaMotte AM-21 Water Pollution Detection Outfit - Manual (Page 24)

Overhead Projection Demonstration
Quantity Contents Code
30 g *Chromate Indicator Powder *4431-G
1 Spoon, 0.5 g 0698
1 Test Tube, 5.0 mL 0230
1 Demonstration Stage, six cell 1038
1 Spatula 0691
WARNING: Reagents marked with a * are considered to be potential health hazards.
To view or print a Material Safety Data Sheet (MSDS) for these reagents see MSDS CD
or www.lamotte.com. To obtain a printed copy, contact LaMotte by email, phone or fax.
Procedure
1. Place the demonstration stage (1038) on the overhead projector and
turn on the projector light.
2. Fill test tube (0230) to the 5.0 mL line with sample water, and transfer to
a cell on the demonstration stage (1038). Repeat this operation so that
two cells are filled with 5.0 mL of the sample water. One cell will act as a
control and no chromate indicator is added to it.
3. Use the 0.5g spoon (0698), to add one level spoonful of Chromate
Indicator (4431) to the cell to be used for measuring the test sample. Stir
the mixture with the spatula (0691) until all the powder is dissolved. If a
trace of chromium or chromate is present in the water sample, a slight
pink color will develop. Greater amounts of chromium or chromate in
the water sample will cause a deep red or purple color to form.
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