Radium salt water

Ra.don Sepa.ra.tion, Owing to its short half-life, radon is normally prepared close to the point of use in laboratory-scale apparatus. Radium salts are dissolved in water and the evolved gases periodically collected. The gas that contains radon, hydrogen, and oxygen is cooled to condense the radon, and the gaseous hydrogen and oxygen are pumped away. 

Radon can be isolated from radium by several methods. An aqueous solution of radium salt such as radium bromide is heated, liberating radon. Radioactive bombardment then decomposes water to oxygen and hydrogen. Radon is separated from the gaseous mixture by condensation in tiny tubes placed in liquid air. The tubes then are sealed by melting. A gold or platinum coating is applied to form the radon seeds used in radiation therapy. 

Radium is chemically similar to barium it displays a characteristic optical spectrum its salts exhibit phosphorescence in the dark, a continual evolution of heat taking place sufficient in amount to raise the temperature of 100 times its own weight of water 1°C every hour and many remarkable physical and physiological changes have been produced. Radium shows radioactivity a million times greater than an equal weight of uranium and. unlike polonium, suffers no measurable loss of radioactivity over a short period of time (its half life is 1620 years). From solutions of radium salts, there is separable a radioactive gas radium emanation, radon, which is a chemically ineit gas similai to xenon and disintegrates with a half life of 3.82 days, with the simultaneous formation of another radioactive element, Radium A (polonium-218). 

Radium in water exists as a stable divalent ion it probably does not hydrolyze nor is it significantly influenced by oxidation-reduction reactions (Ames and Rai 1978). The solubility of radium salts is increased with increasing pH levels. 

IV. From Water by Radioactive Substances.—Although radium salts will decompose hydrogen peroxide, they likewise form this substance when their rays act upon water.8 Kernbaum9 concluded that the /3 rays are the most effective agents, and suggested that the reaction takes places as follows ... 

Radium Barium Platinocyanide.—-Since the majority of platino-cyanides fluoresce under the influence of radiations from radioactive substances, the radium salt should be self-luminous. The radium barium salt was prepared1 by dissolving radioactive barium chloride in water and boiling the solution with excess of silver platinocyanide. After filtering off insoluble silver salts the solution was allowed to crystallise in a desiccator. 

The white solid oxides MjO and M 0 are formed by direct union of the elements. The oxides MjO and the oxides M"0 of calcium down to radium have ionic lattices and are all highly basic they react exothermically with water to give the hydroxides, with acids to give salts, and with carbon dioxide to give carbonates. For example... 

Lithium, sodium, beryllium, magnesium, calcium, and radium are all made industrially by the electrolysis of their molten chlorides. These salts are all soluble in water, but aqueous solutions are not used for the electrolytic process. Explain why. 

Uranium mineral first is digested with hot nitric acid. AH uranium and radium compounds dissolve in the acid. The solution is filtered to separate insoluble residues. The acid extract is then treated with sulfate ions to separate radium sulfate, which is co-precipitated with the sulfates of barium, strontium, calcium, and lead. The precipitate is boiled in an aqueous solution of sodium chloride or sodium hydroxide to form water-soluble salts. The solution is filtered and the residue containing radium is washed with boiling water. This residue also contains sulfates of other alkahne earth metals. The sohd sulfate mixture of radium and other alkahne earth metals is fused with sodium carbonate to convert these metals into carbonates. Treatment with hydrochloric acid converts radium and other carbonates into chlorides, all of which are water-soluble. Radium is separated from this solution as its chloride salt by fractional crystallization. Much of the barium, chemically similar to radium, is removed at this stage. Final separation is carried out by treating radium chloride with hydrobromic acid and isolating the bromide by fractional crystallization. 

Rama, and Moore, W.S. (1996) Using radium quartet for evaluating groundwater input and water exchange in salt marshes. Geochim. Cosmochim. Acta 60, 4645-4652. 

The radium barium salt recovers its fluorescent properties upon recrystallisation, and the effect is enhanced by contact with its own saturated aqueous solution, probably because the water prevents the alteration referred to. 

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. ... 

Properties. — Radium is a white metal, with a melting point of about 700°. It blackens rapidly in the air due to the formation of the nitride. It chars paper, and reacts readily with water, forming the hydroxide. It dissolves easily in HC1. The element displays all the phenomena of radioactivity which are characteristic of its salts. On this account it is customary to speak of the amount of radium element present in a compound... 

In water and sediments, the time to chemical steady-states is controlled by the magnitude of transport mechanisms (diffusion, advection), transport distances, and reaction rates of chemical species. When advection (water flow, rate of sedimentation) is weak, diffusion controls the solute dispersal and, hence, the time to steady-state. Models of transient and stationary states include transport of conservative chemical species in two- and three-layer lakes, transport of salt between brine layers in the Dead Sea, oxygen and radium-226 in the oceanic water column, and reacting and conservative species in sediment. 

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