Radium -nitrate

Write the chemical formulas for (a) gold(III) nitrate, cobalt(II) nitrate, bismuth(V) nitrate, radium nitrate, tin(IV) nitrate, and arsenic(III) nitrate, (b) Write the sulfite compounds. 

Radium nitrate, Ra(N03)2, is soluble and is formed by dissolving the carbonate in HN03. 

The importance of isomorphism can be illustrated by the coprecipitation of Ra in trace quantities with Sr in strontium nitrate. If the precipitation is carried out at 34°C, the radium coprecipitates since at this temperature the strontium precipitates as Sr(N03)2 with which radium nitrate is isomorphous. However, if the precipitation occurs at 4°C, the strontium crystallizes as Sr(N03)2 4H20 and is no longer isomorphous with Ra(N03)2. Due to the lack of isomorphism the radium is not coprecipitated at 4°C. 

Under favorable circumstances, an initial precipitation reaction can be selected that will separate the radionuclide of interest from most contaminants. An example from the group separations in Table 3.2 is the precipitation of strontium nitrate in concentrated nitric acid. The element of interest may be accompanied by several other elements, usually in the same periodic group, as indicated in the table. Barium and radium nitrate, for example, are also insoluble. If such specific precipitation reactions can be applied directly, the only additional processes will be separation from these similar elements and preparation of the counting source. 

Major constituents (greater than 5 mg/L) Minor constituents (O.Ol-lO.Omg/L) Selected trace constituents (less than 0.1 mg/L) Bicarbonate, calcium, carbonic acid, chloride, magnesium, silicon, sodium, sulfate Boron, carbonate, fluoride, iron, nitrate, potassium, strontium Aluminum, arsenic, barium, bromide, cadmium, chromium, cobalt, copper, gold, iodide, lead, Uthium, manganese, molybdenum, nickel, phosphate, radium, selenium, silver, tin, titanium, uranium, vanadium, zinc, zirconium... 

In 1901 Demarcay made an elaborate series of fractionations of samarium magnesium nitrate which resulted in the discovery of a new earth, europia (3, 31, 59). Since he could read a complex spectrum like an open book, he was frequently called upon to pass judgment on supposedly new elements, and was the first to observe the new lines of radium in some barium salts brought by Pierre Curie. 

Property Radium Bromide Carbonate Chloride Hydroxide Iodate Nitrate Sulfate... 

Interest in the subject was revived in 1907 by Ramsay s 7 announcement of the development of spectroscopic quantities of lithium in solutions of cupric sulphate or nitrate exposed to the radium emanation. In control experiments made without the emanation no lithium was detected. ilme. Curie and Mile. Gleditsch8 repeated Ramsay s experiments, employing vessels of platinum instead of glass, but failed to detect the development of even a trace of lithium. They attribute Ramsay s results to solution of lithium present in the glass of his apparatus. Mile. Gleditsch9 detected the presence of lithium in a sample of pitchblende from Joachimsthal, as well as in other radioactive minerals, but failed to find any simple relationship between the proportion of lithium and copper present in the minerals examined. The results10 are summarized in the table ... 

Perman2 exposed solid cupric nitrate and sulphate and auric chloride, contained in quartz vessels at a pressure of 0-1 mm., to the action of radium bromide for four months, but in no instance could the development of lithium be detected by the spectroscope. 

Potassium and many of its salts are said to exhibit radioactivity, the amount of radium present in a gram of the chloride, sulphate, carbonate, or nitrate being given12 as 3 X 10-u. Some authorities deny the existence of radioactive properties. 

The known inorganic chemistry of radium does not differ significantly from that of barium. The isotopes of radium are compiled in Table 4. The chloride, bromide, and nitrate salts of Ra are all water soluble. For example, RaCb (24.5 g/lOOmL H2O at 25 °C) has a comparable solubility to BaCl2 (30.7 g). This slight difference is the primary mode of separation of Ra from Ba. Barium sulfate frequently plays the role of a carrier for Ra. The solubility of RaS04 (2.1 x 10 " g/lOOmL H2O at 25 °C) is perhaps the lowest of any of the group 2 elements. Other aqueous insoluble salts of Ra include and Cr04. ... 

Treatment of Uranium Minerals.—The chief source of uranium compounds is uraiiinite, but at the present time the working up of all uranium minerals has for its main object the extraction of radium, and the uranium salts are merely produced as by-products. The methods in use ary according to the nature of the desired product, which may be ammonium or sodium diuranate, or iiranyl nitrate. 

Nozaki Y. and Yamamoto Y. (2001) Radium 228 based nitrate fluxes in the eastern Indian Ocean and the South China Sea and a silicon-induced alkalinity pump hypothesis. Global Biogeochem. Cycles 15, 555-567. 

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