Mercury sulphate

Digestion. 20-25 mg. of the substance whose nitrogen content is to be estimated are weighed out in a stoppered weighing-tube and then transferred to the flask L that has been previously dried in an oven at izo C. With care, the substance may be transferred directly into the bulb of the flask without any adhering to the sides. If any material sticks on the way down, the flask should be tapped gently to cause the substance to fall to the bottom. 2 G. of the catalyst mixture (32 g. of potassium sulphate, 5 g. of mercury sulphate and ig. of selenium powder, well mixed) are added and 3 ml. of A.R. cone, sulphuric acid are measured out carefully and poured into the digestion... 

Thus films can be divided into two groups according to their morphology. Discontinuous films are porous, have a low resistance and are formed at potentials close to the equilibrium potential of the corresponding electrode of the second kind. They often have substantial thickness (up to 1 mm). Films of this kind include halide films on copper, silver, lead and mercury, sulphate films on lead, iron and nickel oxide films on cadmium, zinc and magnesium, etc. Because of their low resistance and the reversible electrode reactions of their formation and dissolution, these films are often very important for electrode systems in storage batteries. 

The main advantage of Weston s cell was its insensitivity to temperature, and the emf of almost 1 V to be precise, 1.0183 V at 20 °C. It is usually constructed in an Id-shaped glass vessel. One arm contains a cadmium amalgam electrode beneath a paste of hydrated cadmium sulphate (3CdS04 5H20) cadmium sulphate and mercury sulphate. The other arm contains elemental mercury. Its schematic is Cd(Hg) CdS04(aq), Hg2S04 Hg. 

Neuberg and Popowsky, as also Abderhalden and Kempe, have introduced a few alterations in the procedure, such as evaporation in vacuo, and Levene and Rouiller suggested in 1906 that the tryptophane, on account of its proneness to decompose on evaporation of its solution with consequent loss, be estimated colorimetrically the mercury sulphate precipitate is decomposed, and the solution, freed from hydrogen sulphide, is titrated with bromine water in presence of amyl alcohol. Both cystine and tyrosine react with bromine water the latter can, however, be removed, but for the former a correction has to be made. Up to the present no values concerning the amount of tryptophane in various proteins have appeared, and it will be of interest to see if the values so obtained are very much higher than those obtained by crystallisation of the tryptophane. 

Reagents, (a) Mercury sulphate solution obtained by dissolving 5 grams of mercuric oxide in ioo c.c. of water and 20 c.c. of concentrated sulphuric acid. 

Nitrates of these cations are very soluble. Among sulphates lead sulphate is practically insoluble, while silver sulphate dissolves to a much greater extent. The solubility of mercury sulphate lies in between. Bromides and iodides are... 

Mercurous sulphate 892 4 Basic mercuric Sulphate protosulohate of mercury subsulphate of mercury sulphate of the suboxide of mercury turoeth mineral yellow subsulphate of mercury. 

EINECS 231-992-5 HSDB 1247 Mercuric bisulphate Mercuric sulfate Mercuric sulphate Mercurous bisulphate Mercury bisulfate Mercury disulfate Mercury persulfate Mercury sulfate (HgSOk) Mercury sulphate Mercury(ll) sulfate Mercury(ll) sulfate (1 1) Sulfate mercurique Sulfuric acid, mercury(2- ) salt (1 1). Catalyst in the conversion of acetylene to acetaldehyde, extracting gold and silver from roasted pyrites, battery electrolyte. Solid dec 450 d = 6.47 reacts with H2O LDm (rat orl) n 57 mg/kg. Atomargic Chamatals Lancaster Synthesis Co. Noah Cham. 

Currently Eh is measured by comparing electric potential of water with potential of comparison electrode. For this purpose in the solution is submerged indicator platinum electrode, which is connected through a voltmeter with nonpolarizable comparison electrode. As the latter are used mercury chloride, chlorine-silver, mercury-sulphate and other electrodes calibrated against solutions with known Eh values. For the calibration is usually used buffer Zobell solution (water solution of 0.003 moles KjFefCN), 0.003 moles of K Fe(CN)g in 0.1 mole of KCl), which under standard conditions has Eh = 430 mV. 

Weston cell (cadmium cell) A type of primary voltaic cell, which is used as a standard it produces a constant e.m.f. of 1.0186 volts at 20°C. The cell is usually made in an H-shaped glass vessel with a mercury anode covert with a paste of cadmium sulphate and mercury(l) sulphate in one leg and a cadmium amalgam cathode covered with cadmium sulphate in the other leg. The electrolyte, which connects the two electrodes by means of the bar of the H, is a saturated solution of cadmium sulphate. In some cells sulphuric acid is added to prevent the hydrolysis of mercury sulphate. It is named after Edward Weston (1850-1936). 

Measure out 5 ml mercury sulphate solution into the reaction flask. Add a measured 20 ml of the sample to be tested and mix carefully. 

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