GOST 16883.1-71
GOST 16883.1−71 Silver-copper-zinc solders. Method for determination of silver content (with Amendments No. 1, 2)
GOST 16883.1−71*
Group B59
STATE STANDARD OF THE USSR
SILVER-COPPER-ZINC SOLDERS
Method for determination of silver content
Silver-copper-zinc solders. Method for determination of silver content
AXTU 1709
Date of introduction 1972−07−01
The decision of the State standards Committee of the USSR Council of Ministers dated 9 April 1971 N 713 introduction installed with 01.07.72
Proven in 1985 by the Resolution of Gosstandart from
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** Expiration removed by Protocol No. 5−94 of the Interstate Council for standardization, Metrology and certification (I & C N 11/12, 1994). — Note the manufacturer’s database.
INSTEAD of OST 2987 in the determination of silver
* REVISED (July 1986) with Amendments No. 1, 2 approved in January 1981, February 1985 (IUS 6−81, 5−85).
This standard applies to silver-copper-zinc solders and sets potentiometric method for the determination of silver (at a mass fraction of silver from 8.0% to 71%).
The method is based on potentiometric titration of silver ion with a sodium chloride solution with the use of automatic titration unit. As the reference electrode used silver chloride electrode EVL-1МЗ filled with a saturated solution of nitrate of potassium. The indicator electrode is a wire of silver.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 22864−83.
(Changed edition, Rev. N 1).
2. APPARATUS, REAGENTS AND SOLUTIONS
pH-meter-millivoltmeter.
The magnetic stirrer.
Burette with automatic zero setting capacity of 50 cm.
The block automatic titration laboratory.
Nitric acid GOST 4461−77 diluted 1:1.
Silver brand SR 999,9 according to GOST 6836−80*.
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* On the territory of the Russian Federation GOST 6836−2002. — Note the manufacturer’s database.
Sodium chloride according to GOST 4233−77, 0.1 N. solution. For the preparation of 0.1 N. sodium chloride solution used fiksanal 0.1 g/EQ. In the absence of fiksanala dissolve 5,85 g of sodium chloride in 1 DMof water.
To install the titer of the 0.1 n solution of sodium chloride of silver weighed three hanging silver brand 999.9 weight 0,45−0,47 g of Sample was placed in beakers with a capacity of 250 cmand dissolved by heating in 10 cm
diluted 1:1 nitric acid, then heated to remove oxides of nitrogen and dilute with water to 100 cm
. The solutions were titrated as described in sec. 4.
3. PREPARATION FOR ASSAY
Three sample alloy at 1.0 g (for the mass concentration of silver up to 50%) or 0.5 g (at a mass proportion of silver over 50%) are placed in the beakers with a capacity of 250 cmand dissolved by heating in 10 cm
diluted 1:1 nitric acid, then heated to remove oxides of nitrogen and dilute with water to 100 cm
.
(Changed edition, Rev. N 2).
4. ANALYSIS
Prepared for the analysis of the solution is titrated potentiometric method of 0,1 n solution of sodium chloride to a predetermined potential difference on the block automatic titration.
(Changed edition, Rev. N 1).
5. CALCULATION OF RESULTS OF ANALYSIS
5.1. Mass fraction of silver () in percent is calculated by the formula
where — the amount of sodium chloride solution consumed for titration, cm
;
the titer of a solution of sodium chloride, expressed in g/cm
of silver;
— hanging,
5.2. Allowable absolute discrepancies in the results of parallel measurements at a confidence probability of 0.95 should not exceed 0.15%.
(Changed edition, Rev. N 2).
