Perhaps the most longstanding use of mercury not based primarily on its alluring physical properties was in amalgamation. A famous example of such gradual poisonings resulted from the use of mercuric nitrate in processing the animal skins used in 18th and 19th century hatmaking, which led to the coining of the phrase “mad as a hatter.” Increasing recognition of the dangers of chronic mercury exposure and of widespread environmental contamination due to mercury-containing products has driven significant reduction in many classical uses of the element. It has long been recognized that acute inhalations of mercury can lead to significant symptoms, but it is now understood that the slow elimination of most forms of mercury from the body ensures that even low levels can cause severe damage if chronic exposure allows for significant accumulation. Medical uses of mercury are so embedded in some traditional healing practices that some practitioners still recommend the consumption of the mercury ore cinnabar for specific ailments or as a supplement for general health. Its earliest uses were ceremonial, decorative, or medical it was used in medical ointments and elixirs, cosmetics, and reflecting pools, and frequently was buried in large quantities alongside dead rulers. The element was known to ancient civilizations, and though its metallic nature was not initially understood, its unique properties led it to be almost invariably seen as special or even imbued with magical powers. Its chemical symbol Hg arises from the latin hydragyrum, meaning “liquid-silver”, and its common name was borrowed from the Roman god Mercury. Mercury is the only metal that is liquid at standard temperature and pressure, a property that results from a unique electron configuration that gives rise to unusually weak metallic bonds. 53, 710 (1963).American Elements: The Materials Science Company™ | Certified bulk & lab quantity manufacturer of metals, chemicals, nanoparticles & other advanced materials 35, 74 (1996). Gives wavelengths with uncertainties of about 0.001 Å for 19 lines (2536 - 5791 Å) emitted by Hg pencil-type lamps. Lide, Ed., CRC Press, Inc., Boca Raton, FL (1996).Ĭ. Wiese, NIST Atomic Transition Probability Tables, CRC Handbook of Chemistry & Physics, 77th Edition, D. in the region 2536-5791 Å show the pencil-lamp Hg wavelengths to be systematically longer than the values of Burns et al. We also note that the wavelengths given here should not be used for calibrations based on lines from pencil-type lamps if uncertainties smaller than 0.01 Å are desired measurements by Sansonetti et al. in the 2536-5791 Å region the resulting standard deviation of 0.003 Å between the two sets of measurements may be at least partly due to line-shape effects. have made high-accuracy measurements of 26 of the Hg I wavelengths measured by Burns et al. Using a low-pressure electrodeless lamp source, Sansonetti et al. Mainly because such effects can affect the measured wavelengths, we have given no more than three decimal places for the lines of Hg I. As a result, the line shapes can vary according to spectrometer resolution, observation time, etc. 40, 339 (1950). The lines of natural Hg I are broadened by hyperfine and isotopic structures.
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