Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 72
72
Name: TETRASODIUM PYROPHOSPHATE
CAS No: 7722-88-5
Chemical Formula: Na4P2O7
Formula Weight: 266
Description:
White, odorless crystals or granules.
Use:
Used as corrosion inhibitor.
Purity Requirements:
NAS/CWTC 039/82
Na4P2O7 · 1OH2O
446
Analyses of available grades of tetrasodium pyrophosphate
show the presence of cadmium and lead but at levels far
below that which would necessitate RMIC values based on a
maximum dosage of 14 mg/liter.
Bulk Sample Collection:
Sample in accordance with the Standard for Sodium Tripoly-
phosphate, AWWA B503-78, American Water Works Association,
Denver, Colorado (1978).
1
Analytical Sample Preparation:
Weigh out 2.5 g of tetrasodium pyrophosphate. In a
150-ml acid-washed beaker, dissolve the sample in 100 ml
of deionized distilled water. Under a hood, acidify the
solution with concentrated HNO3 to a pH of less than
2. Gently heat the solution to reduce the volume below
100 ml, making certain that it does not boil. Quanti-
OCR for page 73
73
tatively transfer to a 100-ml acid-washed volumetric
flask and make to volume with deionized distilled water.
Process a reagent blank by the same procedure.
Sample Analyses:
The analyses are to be performed on the tetrasodium
pyrophosphate solution in accordance with:
Standard Methods for the Examination of Water and Waste-
water, 15th Edition, American Public Health Association,
Washington, D.C. (1981).
Cadmium
Lead
Section 304
Section 304
Representative terms from entire chapter:
distilled water
