The Nature of Mercury I

Physicochemical measurements are used to establish whether Hg(I) in its salts is represented by Hg or by the (Hg-Hg) ion. If X-ray diffraction measurements are 

An easy experiment to establish the nature of the Hg(l) ion is to compare the molar conductivity of Hg(l) nitrate to that of KNO3 and Ba(N03)2 since the latter is uni-divalent electrolyte whereas potassium nitrate is a uni-univalent electrolyte. 

Weigh out accurately 7.02 g of purest mercuiy(I) nitrate dihydrate, 1.26 g of purest potassium nitrate and 3.27 of purest barium nitrate. Dissolve each solid separately in conductivity water and make up to 250 cm in a volumetric flask. Use a conductivity cell with platinised electrodes, some centimetres apart which had been cleaned and stored filled with conductivity water. Rinse the cell with the mercury(I) solution several times, place in a thermostat at 298 K, allow to equilibrate thermally and measure its resistance (Sec.2.5.2). Repeat the same steps using the other two solutions and compare the data from the three solutions. What conclusions can be drawn from your results  

Grind mercury (I) chloride to a fine powder. Measure its magnetic susceptibility (Sec.2.1.3). How does the result help to elucidate the nature of Hg(l) ions  

The chalcogenides of the three metals are semiconductors and generally act as photocatalysts in oxidations and/or reductions induced by radiation. On the other hand, Hg(II) and Cd(II) can be photocatalytically reduced under suitable conditions. Care has to be taken to allow for the adsorption of the ions by the powdered catalyst. 

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