Cadmium sulphate hydrate

Standard cadmium ion solution. Prepare a standard cadmium ion solution containing ca 0.04 mg mL 1 Cd using hydrated cadmium sulphate. 

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. 

Tetrammino-cadmium Sulphate, [Cd(NH3)4 S04.2lI20, is prepared by evaporation of an aqueous ammoniaeal solution of cadmium sulphate, or by passing ammonia gas into a well-cooled ammoniaeal solution of the sulphate. A hydrate containing four molecules of water may be obtained, when an aqueous ammoniaeal solution of cadmium sulphate is poured into alcohol and the ammonia allowed to evaporate in air. The hexammine is prepared by the method already described for hexammino-sdne chloride. It loses ammonia when fused and completely decomposes water hydrolyses it with precipitation of cadmium hydroxide. 

Cadmium Arsenates.—The hydrated normal cadmium orthoarsenate, 2Cd3(As04)2.3H20, falls as a white voluminous precipitate on adding alkali to a solution of cadmium mono- or di-hydrogen arsenate in hydrochloric acid,4 or on addition of sodium orthoarsenate to a solution of cadmium sulphate.5 On drying at 100° C. the anhydrous salt remains. 

BROMIC ACID CADMIUM CYANIDE CALCIUM BISULFIDE CALCIUM BISULFITE CALCIUM CARBONATE CALCIUM CHLORIDE CALCIUM HYDROXIDE CALCIUM HYPOCHLORITE CALCIUM NITRATE CALCIUM SULPHATE CARBON DIOXIDE CARBON MONOXIDE CARBONIC ACID CASTOR OIL CAUSTIC POTASH CAUSTIC SODA CHLORAL HYDRATE CHLORIC ACID. 20% CHLORIDE (WATER) CHLORINE WATER CHROME ALUM CITRIC ACID COPPER CARBONATE COPPERCHLORIDE COPPER CYANIDE COPPER FLUORIDE... 

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