osmium: Quick Facts

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Also Known As	Os

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A labeled diagram of the periodic table entry for osmium shows its atomic number 76, symbol Os, atomic weight 190.23, electron configuration, and physical state as a solid transition metal with a hexagonal crystal structure and weakly acidic oxides.

Figure 7: The mass spectrum of osmium. This recorder trace was obtained with an electron multiplier detecting OsO3−. The leftmost and rightmost peaks were recorded with the detector gain set at a value 100 times that used for the rest of the spectrum; this change is marked by the change in the baseline position. The small satellite peaks to the left are those of the low abundance oxygen isotopes 17O and 18O; the osmium isotopes are, from left to right, 184Os, 186Os, 188Os, 189Os, 190Os, and the satellite peaks of 192Os.

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osmium-186 osmium-187 ruthenium chemical element transition metal hydrogen carbon sodium nitrogen sulfur phosphorus boron iodine halogen fluorine

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