Copper sulphate test

The evaluation of heat treatments or the effectiveness of stabilisation by limiting carbon content of these stainless steels can be determined by subjecting specimens to the ASTM standardised acid copper sulphate test or boiling nitric acid test (ASTM A262 1986 see also Sections 9.5 and 1.3). 

Acid copper sulphate test t 16 wt.% H2SO4 -1-100 g/l CuSO, (-1- metallic copper) 72 h exposure to boiling solution 1. Appearance of sample upon bending 2. Electrical resistivity change 3. Change in tensile properties -1- 0-30 to -1- 0-58 Chromium-depleted area... 

Ammonium tetrathiocyanatomercurate(II)-copper sulphate test. The faintly acid (sulphuric acid or acetic acid) solution is treated with 0-1 ml 0 25m copper sulphate solution, followed by 2 ml ammonium tetrathiocyanatomercurate(II) reagent. A violet precipitate is obtained. The test is rendered still more sensitive by boiling the mixture for 1 minute, cooling and shaking with a little amyl alcohol the violet precipitate collects at the interface. Iron salts produce a red colouration this disappears when a little alkali fluoride is added. 

Ammonium tetrathiocyanatomercurate(II)-copper sulphate test Acidify the solution faintly with a few drops of m sulphuric or 2m acetic acid. Add... 

The aldehyde may be distinguished fiom the ketone by its reducing action on alkaline copper sulphate, ammonia-sih er nitrate and by SchifPs test (see Reactions, p. 67). 

Oxidation-reduction potential Because of the interest in bacterial corrosion under anaerobic conditions, the oxidation-reduction situation in the soil was suggested as an indication of expected corrosion rates. The work of Starkey and Wight , McVey , and others led to the development and testing of the so-called redox probe. The probe with platinum electrodes and copper sulphate reference cells has been described as difficult to clean. Hence, results are difficult to reproduce. At the present time this procedure does not seem adapted to use in field tests. Of more importance is the fact that the data obtained by the redox method simply indicate anaerobic situations in the soil. Such data would be effective in predicting anaerobic corrosion by sulphate-reducing bacteria, but would fail to give any information regarding other types of corrosion. 

British Standard Method for Determination of Resistance to Intergranular Corrosion of A ustenltic Stainless Steels Copper sulphate-Sulphuric acid Method (Moneypenny Strauss Test) BS 5903 (1980)... 

Various types of reference electrodes have been considered in Section 20.3, and the potentials of these electrodes and their variation with the activity of the electrolyte are listed in Table 21.7, Chapter 21. It is appropriate, however to point out here that the saturated calomel electrode (S.C.E.), the silver-silver chloride electrode and the copper-copper sulphate electrode are the most widely used in corrosion testing and monitoring. 

Test methods for determining electrolytic corrosion with electrical insulating materials Method for determination of resistance to intergranular corrosion of austenitic stainless steels copper sulphate-sulphuric acid method (Moneypenny Strauss test) Specification for electroplated coatings of tin/lead alloys... 

Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 1 Corrosion test in nitric acid medium by measurement of loss of mass (Huey test) Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 2 Corrosion test in a sulphuric acid/copper sulphate medium in the presence of copper turnings (Moneypenny Strauss test)... 

Prepare 30-fold and 50-fold dilutions of the test solution. Add 1.25 ml of a mixture prepared the same day by combining 2.0 ml of a 20 g/1 solution of copper sulphate R in water R, 2.0 ml of a 40g/l solution of sodium tartrate R in water R and 96.0 ml of a 40 g/1 solution of sodium carbonate R in 0.2M sodium hydroxide to test tubes containing 1.5ml of water R (blank), 1.5ml of the different dilutions of the test solution or 1.5 ml of the reference solutions. Mix after each addition. After approximately 10 min, add to each test-tube 0.25 ml of a mixture of equal volumes of water R and phosphomolybdotungstic reagent R. Mix each addition. After approximately 30 min, measure the absorbance (2.2.25) of each solution at 750 nm using blank as the compensation liquid. Draw a calibration curve (from the absorbances of the eight reference solutions the corresponding protein contents and read from the curve the content of protein in the test solution. 

Copper Sulphate Pentahydrate. Calculate what amount of copper sulphate crystallohydrate (blue vitriol) has to be taken for 10 ml of water to prepare a solution saturated at60°C (see Appendix 1, Table 1). Bring the solution obtained at the indicated temperature almost up to boiling and rapidly filter it through a fluted filter on a funnel for hot filtration (the funnel must be hot). Close the test tube with the filtrate with a piece of cotton wool. If crystals have formed in the filtrate, dissolve them by careful heating. Cool the solution and introduce a minute crystal of the initial salt into it. What is observed Does the temperature of the solution change ... 

Precipitation with copper sulphate (see p. 200) also affords a test which is considerably more sensitive than.the acidification test, and the result is not affected by the presence of polythionates. 

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