GOST 1429.9-77
GOST 1429.9−77 Solders tin-lead. Method for the determination of aluminium (with Amendments No. 1, 2)
GOST 1429.9−77*
Group B59
STATE STANDARD OF THE USSR
SOLDERS TIN-LEAD
Method for the determination of aluminium
Tin-lead solders.
Method for the determination of aluminium*
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.
REPLACE GOST 1429.9−69
* REPRINT March 1983 with the Change in N 1, approved in January 1983; Post. N 325 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 establishes photocolorimetric method of determining the mass fraction of aluminum in the tin-lead solder (with a mass fraction of aluminum from 0.0005 to 0.002%).
The method is based on dissolving the sample in a mixture of hydrochloric, bromatological acid and bromine, the Stripping of tin, antimony and arsenic, separation of interfering elements by diacetamido, the formation of colored compounds of aluminum with eryhromycin and measuring the optical density of the colored complex.
(Changed edition, Rev. N 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1429.0−77.
2. APPARATUS, REAGENTS AND SOLUTIONS
Photoelectrocolorimeter or spectrophotometer.
a pH meter.
Hydrochloric acid by the GOST 3118−77, diluted 1:1 and 1 mol/DMsolution.
Bromatologia acid according to GOST 2062−77.
Nitric acid GOST 4461−77 and diluted 1:1.
Sulfuric acid GOST 4204−77, diluted 1:1 and 1:24.
Bromine according to GOST 4109−79.
Mix to dissolve, is prepared as follows: to 45 cmof concentrated hydrochloric acid poured 45 cm
bromatological acid and carefully add 10 cm
of bromine.
The thioacetamide solution, a mass fraction of 1% freshly prepared (optionally filtered).
Hydrogen peroxide according to GOST 10929−76.
Acetic acid GOST 61−75.
Urea according to GOST 6691−77.
Iron chloride; prepared as follows: 0.05 g of iron, reduced hydrogen, dissolved in 5 cmof concentrated hydrochloric acid with a few drops of hydrogen peroxide. After decomposition of the excess amount of peroxide, the solution was cooled, transferred into a measuring flask with volume capacity of 1000 cm
and was adjusted to the mark with water.
Sodium hydroxide according to GOST 4328−77, a solution of 2 mol/DM; prepared as follows: 80 g of sodium hydroxide dissolved in water, cooled, transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water, mix.
Thioglycolic acid, 96%, is prepared as follows: to 10 cmthioglycolic acid was added 12 cm
of acetic acid, diluted with water, transferred into a measuring flask with volume capacity of 1000 cm
, mix.
Ammonium acetate according to GOST 3117−78.
Sodium acetate, anhydrous.
Buffer solution; prepared as follows: 46.4 g of ammonium acetate and 18.2 g sodium acetate dissolved in water with stirring. The solution is transferred into a measuring flask with volume capacity of 1000 cmand bring the water almost to the mark. To obtain pH 6, if necessary, is added either a solution of 2 mol/DM
sodium hydroxide or acetic acid and then adjusted to the mark with water. the pH of the prepared solution is controlled using a pH meter.
Eryhromycin R, the solution is prepared as follows: 0.35 g of erioglaucine R dissolved in 2 cmof concentrated nitric acid with constant stirring for 2 minutes, add 60 cm
of water, 0.3 g of urea, the contents stirred and allowed to stand in a dark place. After 24 hours the solution is filtered through a dense filter into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water, mix. The solution is stored in container made of dark glass.
Aluminium primary brand А999 according to GOST 11069−74*.
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* On the territory of the Russian Federation GOST 11069−2001. — Note the manufacturer’s database.
Standard solutions of aluminium.
Solution a (basic); prepared as follows: 0.1 g of aluminium is placed in a beaker with a capacity of 100 cm, dissolved in 20 cm
of hydrochloric acid diluted 1:1, transfer the solution into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water, mix. 1 cm
of the solution contains 0.0001 g of aluminum.
Solution B is prepared as follows: 5.0 cmmortar And placed in a volumetric flask with a capacity of 100 cm
, adjusted to the mark with water, mix. 1 cm
of solution B contains 0,000005 g of aluminum.
Solution B is prepared immediately before use.
(Changed edition, Rev. N 1, 2).
3. ANALYSIS
3.1. A portion of the solder mass 1 g is placed in a low glass with a capacity of 250 cmand dissolved under moderate heating in 15 cm
of the mixture of acids to dissolve. After dissolution, the sample solution is gently evaporated until dry, without bringing it to boil. Evaporation with a 10 cm
mixture again. Then add 5 cm
of hydrochloric acid of 1 cm
of bromine and evaporated again to dryness. This operation is repeated again. To the residue poured 5 cm
of nitric acid, diluted 1:1 and boiled until the bromine volatilization, then pour 2 cm
of sulphuric acid diluted 1:1, and evaporated until the appearance of fumes of sulphuric anhydride. The cooled solution was added 25 cm
of water, cover the beaker watch glass, heated to boiling. Pour 10 cm
of a solution of thioacetamide, boil the solution for 10 min, allow sediment to settle and the precipitate is filtered through a dense filter, washed five to six times with sulfuric acid, diluted 1:24. The precipitate is discarded. To filtrate add 1−2 cm
of hydrogen peroxide and evaporated to dryness. The dry residue leached 1 cm
1 n hydrochloric acid solution, poured 5cm
of water and transferred to volumetric flask with a capacity of 100 cm
. Thus washed glass 15 cm
of water, consuming it in two or three divided doses.
To the solution in a volumetric flask are added 1 cmof solution of ferric chloride, 10 cm
of a solution of thioglycolic acid and dropwise 2 n sodium hydroxide solution, to the formation of the purple color of the solution. Then added dropwise 1 n hydrochloric acid solution until the disappearance of color and the excess 2 cm
. Add 20 cm
of a solution of erioglaucine and after 5 min, 30 cm
buffer solution. Bring to the mark with water and after 20 minutes, measure the optical density of the solution on a photoelectrocolorimeter with a green filter (wavelength 530 nm) in a cuvette with a layer thickness of 5 cm. pH of the solution prepared for the measurement of optical density should be at 5.8−6.
As a solution the comparison used the zero solution containing all reagents except the aluminum.
At the same time through the analysis of spend control experience. The aluminum content find the calibration schedule, taking into account the correction for the reagents.
(Modified, edited by
I, ISM. N 1).
3.2. Construction of calibration curve
In a volumetric flask with a capacity of 100 cmeach placed 0; 0,5; 1,0; 2,0; 3,0; 4,0; 5,0 cm
standard solution B, dilute with water to volume of 20 cm
, add 1 cm
of ferric chloride and then analysis is carried out as specified in clause 3.1.
On the found values of optical densities of solutions and their corresponding grades of aluminium to build the calibration graph.
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of aluminium () in percent is calculated by the formula
where is the mass of aluminum was found in the calibration schedule g;
— the weight of the portion,
(Changed edition, Rev. N 2).
4.2. Allowable absolute differences the results of the analysis at a confidence level of 0.95, should not exceed the values given in the table.
| Mass fraction of aluminum, % |
Allowable absolute differences, % |
| From 0.0005 to 0.001 |
0,0003 |
| SV. 0.001 to 0,002 |
0,0005 |
(Changed edition, Rev. N 1, 2).
