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Sample Collection, Storage, and Preservation
Accuracy Check
Silver_PP_Other_CLR_Eng_Ody.fm
Interfering Substance
Manganese
Magnesium
Mercury
Nickel
Zinc
Collect samples in acid-cleaned glass or plastic bottles. Using pH paper,
adjust the pH to 2 or less with Concentrated Nitric Acid (Cat. No. 152-49)
(about 2 mL/liter). Store preserved samples at room temperature for up to 6
months. If the sample contains particulates or only dissolved metal content is
being determined, filter through a 0.45 mm filter at collection. After filtration,
adjust the pH to 2 or less as described above.
Before analysis, adjust the pH to 9–10 with 5.0 N Sodium Hydroxide
(Cat. No. 2450-32). (See step 13–step 14 of the Digestion procedure on page 4.) Do
not use a pH meter because of silver contamination from the electrode. Correct
for volume additions; see Section 3.1.3 Correcting for Volume Additions on page 29.
Standard Additions Method (Sample Spike)
1. After reading test results, leave the sample cell (unspiked sample) in the
instrument.
2. Touch
. Touch
Options
additions procedure will appear.
3. Touch
to accept the default values for standard concentration, sample
OK
volume, and spike volumes. Touch
are accepted, the unspiked sample reading will appear in the top row. See
Standard Additions in the instrument manual for more information.
4. Add 5.00 mL of 1000 mg/L Silver Standard Solution to a 100-mL volumetric
Class A flask. Dilute to volume with deionized water. This is a 50.0 mg/L
standard solution.
5. Prepare three sample spikes. Fill three mixing cylinders (Cat. No. 1896-41)
with 50-mL of sample. Use the TenSette
0.3 mL of standard, respectively, to each sample and mix thoroughly.
6. Analyze each sample spike as described in the procedure above, starting with
the 0.1 mL sample spike. Accept each standard additions reading by touching
. Each addition should reflect approximately 100% recovery.
Read
7. After completing the sequence, touch
the standard additions data points, accounting for matrix interferences. Touch
, then select
View: Fit
the sample spikes and the "Ideal Line" of 100% recovery.
See Section 3.2.2 Standard Additions on page 32 for more information.
(continued)
Interference Levels and Treatments
Negative interference above 19 mg/L
Positive interference above 2000 mg/L
Positive interference above 2 mg/L
Negative interference above 19 mg/L
Negative interference above 70 mg/L
. A summary of the standard
Standard Additions
to change these values. After values
Edit
®
Pipet to add 0.1 mL, 0.2 mL, and
Graph
and touch
Ideal Line
OK
Silver
to view the best-fit line through
to view the relationship between
Page 3 of 6
Silver
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