Strontium atomic energy levels

Bearden JA, Burr AF (1967) Reevaluation of X-ray atomic energy levels. Rev Mod Phys 39 125-142 Beck JW, Edwards R, Ito E, Taylor F, Recy J, Rougerie F, Joannot P, Henin C (1992) Sea surface temperature from coral skeletal strontium/calcium ratios. Science 257 644-647 Bertsch PM, Hunter DB (2001) Applications of synchrotron-based X-ray microprobes. Chem Rev... 

The technology developer, Atomic Energy of Canada Limited (AECL), has compiled cost estimates (in 1994 U.S. dollars) for the CHEMIC process based on treatment of a simulated waste solution contaminated with metals (cadmium and lead at feed concentrations from 1 to 5 mg/liter) and strontium-90 [from 1000 to 2000 becquerel per liter (Bq/liter)]. The target treatment level is <0.014 mg/liter lead, <0.02 mg/liter cadmium, and <10 Bq/liter strontium-90. See Table 1 for estimates associated with this cost analysis. The AECL analysis indicated that costs of the CHEMIC process compared favorably with the estimated costs for treatment using reverse osmosis or fixed-bed ion exchange. 

Harrison JE, McNeill KG, Elaguppillai V. 1972. Strontium and calcium kinetics at the bone level. In International Conference on Strontium Metabolism, ed. Second international conference on strontium metabolism, Glasgow and Strontian, 16-19 August, 1972. TID 4500 59th ed. Health and Safety Laboratory / U S. Atomic Energy Commission, 379-388. 

Feasibility of Separation and Utilization of Caesium and Strontium from High Level Liquid Waste, Technical Reports Series, No. 356, International Atomic Energy Agency, Vienna, 1993. 

The red color in fireworks is the result of having strontium-containing salts in the fireworks bomb. Similarly, the green/blue colors sometimes seen in fireworks arise from copper salts. Based on your understanding of atomic spectra and the colors in fireworks, describe which atom, copper or strontium, has more widely separated energy levels. 

Deduce the number of valence electrons In an atom of lead, and the number of electron shells (energy levels) in an atom of strontium. Explain your answer in terms of the positions of these elements in the periodic table. 

B It has two electrons in its outermost energy level. C Its atomic radius is smaller than that of strontium,... 

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