Strontium ions

Health and Safety Factors. The strontium ion has a low order of toxicity, and strontium compounds are remarkably free of toxic hazards. Chemically, strontium is similar to calcium, and strontium salts, like calcium salts, are not easily absorbed by the intestinal tract. Strontium carbonate has no commonly recognized hazardous properties. Strontium nitrate is regulated as an oxidizer that promotes rapid burning of combustible materials, and it should not be stored in areas of potential fire hazards. 

In the laboratory, strontium chromate (Ksp = 3.6 X 10-5) can be prepared by mixing solutions containing strontium ions and chromate ions, where the concentrations of these ions are high enough to form a precipitate. Decide whether a precipitate will form when... 

Thus, for example a solution containing potassium ions at a concentration of 2000 mg L "1 added to a solution containing calcium, barium, or strontium ions creates an excess of electrons when the resulting solution is nebulised into the flame, and this has the result that the ionisation of the metal to be determined is virtually completely suppressed. 

C07-0112. The bright red color of highway safety flares comes from strontium ions in salts such as Sr(N03)2 and SrC03. Burning a flare produces strontium ions in excited states, which emit red photons at 606 nm and at several wavelengths between 636 and 688 nm. Calculate the frequency and energy (kJ/mol) of emissions at 606, 636, and 688 nm. 

Sasaki, N. and Minato, M. (1983) Effect of the degree of supersaturation upon apparent partition coefficients of lead and strontium ions between BaSOa and aqueous solution. Miner. J., 11, 365-381. 

Sr, as the strontium ion (Sr2+), is used for pain palliation in patients with metastatic bone disease. The strontium ion is a calcium ion mimic, being taken up in metabolically active bone such as cancer. 89Sr is a therapeutic radionuclide with a half-life of 50.53 days, emitting a 1.49 MeV [3 particle on decay. Several recent reviews discuss the use of radionuclides and their complexes as pain palliation agents in metastatic bone disease.18,212-215... 

In the present work, a constant composition method has been used to investigate the growth of HAP from solutions of low supersaturation and in the presence of different background electrolytes. The influence of magnesium and strontium ions both on the rate of crystallization and upon the electrokinetic properties of the crystallite surfaces has also been investigated. 

Strontium sulfate (SrS04) will precipitate when a solution of sodium sulfate is added to a strontium nitrate solution. What will be the strontium ion, Sr2+, concentration remaining after 30.0 mL of 0.10 M Na2S04 solution are added to 70.0 mL of 0.20 M Sr(N03)2 solution ... 

The strontium and sulfate ions react in a 1 1 ratio, so 0.0030 mol of sulfate ion will combine with 0.0030 mol of strontium ion leaving 0.011 mol of strontium in a total volume of 100.0 mL. The final strontium ion concentration is ... 

A road flare contains a salt of strontium to give a red colour to the flame. Write the electron configuration of the strontium ion, with an electron in the least excited energy state. 

Wang, L. M., Zhu, S., Wang, S. X. Ewing, R. C. 2001. Effects of cesium, iodine and strontium ion implantation on the microstructure of cubic zirconia. Materials Research Society Symposium Proceedings, 663, 293-300. 

The cation exchange resin AG MP-50 (BioRad Laboratories) was used for one run, 33-1-9, in anticipation of a greater separation factor for the yttrium-strontium separation. However, the column retained strontium, only slowly releasing it in 6 -12 M HC1. A possible explanation is that strontium ions are adsorbed on the resin inside the large resin pores. When strong acid is passed over the resin, the pores contract, trapping the strontium ions within them. Because of the slow elution of strontium from this resin, AG MP-50 will not be used in the future for strontium purification. 

Strontium ion, Sr 2, can replace calcium ion in bone. If a product of radioactive fallout, strontium-90, 90sr+2, js placed in bone, however, its radioactive decay will destroy both bone and surrounding tissue. 

Scheme 5.4 Schematics of the crown complexed metal species occurring in solutions of ligand 17, strontium ion, ethoxide nucleophile, and carboxylate substrate.

Now there must be twice as many fluoride ions as strontium iocs, so the coordination number of the strontium ion must be twice as large as that of fluoride. Coordination numbers of 8 (Sr2 +) and 4 (F ) are compatible with the maximum allowable coordination numbers and with the stoichiometry of the crystal. Strontium fluoride crystallizes in the fluorite lattice (Fig. 4.3). 

Chlorate ion may be detected and detd as described under Chlorates, Analytical Proceduresand strontium ion as described in Refs 2,3 4. The complete analysis of salt may be done in the manner described by Faber(Ref 1) for Ba chlorate. The method is outlined here under Barium Chlorate, Analytical Procedures, There is no US Military Specification... 

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