ASTM B712-93(2006)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:B712–93(Reapproved2006)
Standard Guide for
Determination of Sodium and Potassium Content For Silver-
Cadmium Oxide Contact Materials
This standard is issued under the fixed designation B712; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.2 Other Document:
Operation Guide for Chemical Analysis of Metals and
1.1 This guide describes procedures for use in conducting
Metal Bearing Ores by Atomic Absorption Spectropho-
analysis of silver-cadmium oxide materials for sodium and
tometry
potassium content. The exact methods for the performance of
this testing are not stated since many different procedures are
3. Significance and Use
equally applicable. This guide points out specific procedures
3.1 This guide is recommended for use in analyzing the
for decreasing the chance of recognized potential errors and
sodium and potassium content of silver-cadmium oxide mate-
specifies methods for increasing the sensitivity of the testing.
rials and is meant to be used in conjunction with standard
1.2 This standard may involve hazardous materials, opera-
methods of atomic absorption spectroscopy.The recommended
tions, and equipment. This standard does not purport to
procedures cite methods for minimizing extraneous sodium
address all of the safety concerns, if any, associated with its
and potassium contamination through use of specific handling
use. It is the responsibility of the user this standard to become
proceduresandshortersamplepreparationmethods.Thisguide
familiar with all hazards including those identified in the
also recommends procedures that prevent the formation of
appropriate Material Safety Data Sheet (MSDS) for this
nonstable and potentially hazardous silver-acetylene com-
product/material as provided by the manufacturer, to establish
pounds.
appropriate safety and health practices, and determine the
applicability of regulatory limitations prior to use. For specific
4. Precautions
precautions see Sections 4 and 6.
4.1 Since silver nitrate reacts with acetylene to form silver
1.3 Whoever uses this standard should consult the Material
acetylide, the guide recommends either alternative flames to
Safety Data Sheet concerning the products involved.
air–acetylene or the removal of silver from solution. Silver
2. Referenced Documents acetylide is unstable and may explode violently upon being
2 disturbed.
2.1 ASTM Standards:
E50 Practices for Apparatus, Reagents, and Safety Consid-
5. Sampling
erations for Chemical Analysis of Metals, Ores, and
5.1 Handle the sample so as to avoid contamination by
Related Materials
3 sodium and potassium; avoid contact with hands.
E663 Practice for Flame Atomic Absorption Analysis
6. Procedures
This guide is under the jurisdiction of ASTM Committee B02 on Nonferrous
6.1 First clean the sample in nitric acid and distilled or
Metals and Alloys and is the direct responsibility of Subcommittee B02.05 on
deionized water to remove extraneous surface contamination.
Precious Metals and Electrical Contact Materials.
Test powder samples as received. Then store the samples in
Current edition approved June 1, 2006. Published June 2006. Originally
such a manner as to minimize contamination.
approved in 1982. Last previous edition approved in 1999 as B712 – 93 (1999).
DOI: 10.1520/B0712-93R06.
6.2 Use a sample size of approximately2gor more for each
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
test.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3 4
Withdrawn. The last approved version of this historical standard is referenced 1982 Annual Book of ASTM Sta
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