GOST 1429.11-77
GOST 1429.11−77 Solders tin-lead. Method for the determination of cadmium (with Amendments No. 1, 2)
GOST 1429.11−77*
Group B59
STATE STANDARD OF THE USSR
SOLDERS TIN-LEAD
Method for the determination of cadmium
Tin-lead solders.
Method for the determination of cadmium*
AXTU 1709**
_________________
* The name of the standard. Changed the wording, Rev. N 2.
** Added, Rev. N 2.
Date of introduction 1978−01−01
The decision of the State standards Committee of the USSR Council of Ministers dated 11 April 1977, N 886 the period of validity set with 01.01.78
PROVEN in 1982 by the Resolution of Gosstandart from 21.01.83 328 N validity extended until 01.01.88**
_____________
** Expiration removed Protocol MGS (IUS N 2, 1993). — Note the manufacturer’s database.
* REPRINT March 1983 with the Change in N 1, approved in January 1983; Post. N 326 from
The Change N 2 approved and put into effect with
Change No. 2 made by the manufacturer of the database in the text IUS N 11, 1987
This standard specifies a volumetric method chelatometric determination of cadmium in tin-lead solder (with a mass fraction of cadmium from 17 to 19%).
The method is based on dissolving the sample solders in a mixture of wine, nitric and hydrochloric acids, complexometric titration of the amount of lead and cadmium in the presence of an indicator kylinalove orange, the titration of lead from another aliquote part of the solution after the binding of cadmium to complex with ortofenantrolinom. Cadmium is determined by difference.
(Changed edition, Rev. N 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1429.0−77.
2. REAGENTS AND SOLUTIONS
Nitric acid GOST 4461−77 and diluted 1:2.
Hydrochloric acid by the GOST 3118−77.
Tartaric acid according to GOST 5817−77, a solution with a mass fraction of 20%.
The mixture of acids I; prepared as follows: to 75 cmof solution with a mass fraction of 20% tartaric acid poured 45 cm
of concentrated nitric acid and 5 cm
of hydrochloric acid.
The mixture of acids II; prepared as follows: to 75 cmof solution with a mass fraction of 20% tartaric acid pour 50 cm
of nitric acid.
Methenamine medical, solution with a mass fraction of 40%.
Orthophenanthroline, an aqueous solution with a mass fraction of 1%; acidified with nitric acid.
Potassium nitrate according to GOST 4217−77.
Selenology orange indicator is prepared as follows: one mass fraction of the indicator are thoroughly mixed in a mortar with 100 mass shares of nitrate of potassium.
Cadmium metal brand CD-00 GOST 22860−77*. A standard solution of cadmium; prepared as follows: 1 g of the cadmium is dissolved with moderate heating in 20−25 cmof nitric acid, diluted 1:2. Heated to remove oxides of nitrogen, cooled, transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water, mix thoroughly.
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* Standards 22860−93. — Note the manufacturer’s database.
1 cmof the solution contains 0.001 g of cadmium.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B) according to GOST 10652−73; 0.02 M solution; prepared as follows: 7.4 g Trilon B dissolved in water, the solution was transferred into a measuring flask with volume capacity of 1000 cm, adjusted to the mark with water and mix.
(Changed edition, Rev. N 1, 2).
3. ANALYSIS
3.1. 0.2 g of solder is placed in a beaker with a capacity of 100 cm, poured 10 cm
of the mixture of acids I (for the analysis of solders stamps BOUGHT 50−18) or 10 cm
of the mixture of acids II (in the determination of cadmium in solders brand POSK-2), are dissolved with moderate heating and cooling. The solution was then transferred to a volumetric flask with a capacity of 250 cm
, was adjusted to the mark with water and mix. Select two aliquote parts of a solution at 100 cm
, one determine the amount of cadmium and lead in the other lead.
3.2. Determining the amount of cadmium and lead
100 cmof solution is placed in a flask with a capacity of 250 cm
, add a spatula tip of indicator kylinalove orange and with stirring, in small portions, pour the solution of hexamine to red-violet color (pH 5,4−5,8). Titrated with a solution of Trilon B before the advent of lemon-yellow color.
The number of solution Trilon B, used for titration of the equivalent amount of content of cadmium and lead.
(Changed edition, Rev. N 2).
3.3. Determination of lead
Second aliquot part of the solution is equal to 100 cm, was placed in a flask with a capacity of 250 cm
, flow 10 cm
solution orthophenanthroline, add selenology orange, solution of hexamine to pH 5,4−5,8 (red-violet colouring of solution) and titrated with a solution of Trilon B till lemon-yellow color of the solution.
The number of solution Trilon B, used for titration, is equivalent to the lead content.
At the same time through the analysis of spend control experience and amend the titration results.
3.4. The installation of the mass concentration of the solution Trilon B
Mass concentration of Trilon B set at a standard solution of cadmium.
25 ml of a standard solution of cadmium was placed in a conical flask with a capacity of 250 cm, add water to volume of 100 cm
, then carry out the analysis as described in section 3.2.
Mass concentration of Trilon B, expressed in g/cmcadmium, calculated by the formula
where is the mass of cadmium contained in 25 cm
standard solution, g;
— volume of solution Trilon B, spent on titration, sm
.
3.3, 3.4. (Changed edition, Rev. N 2).
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of cadmium (a) in percent is calculated by the formula
where — volume of solution Trilon B, used for titration of the amount of lead and cadmium cm
;
— volume of solution Trilon B, used for titration of lead, cm
;
— mass concentration of Trilon B, expressed in g/cm
of cadmium;
— the weight of the portion corresponding to aliquote part of the study solution taken for titration,
(Changed edition, Rev. N 2)
.
4.2. Allowable absolute differences the results of the analysis at a confidence probability of 0.95 should not exceed 0.25%.
(Changed edition, Rev. N 1, 2).
