Standard atomic weight
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The standard atomic weight of a chemical element is the weighted arithmetic mean of the relative isotopic masses of all isotopes of that element weighted by each isotope's abundance on Earth. For exam
Excerpt of an IUPAC periodic table showing the interval notation of the standard atomic weights of boron, carbon, and nitrogen (Chemistry International, IUPAC). Example: the pie chart for boron shows it to be composed of about 20% 10B and 80% 11B. This isotope mix causes the atomic weight of ordinary Earthly boron samples to be expected to fall within the interval 10.806 to 10.821. and this interval is the standard atomic weight. Boron samples from unusual sources, particularly non-terrestrial sources, might have measured atomic weights that fall outside this range. Atomic weight and relative atomic mass are synonyms.
Gold
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Gold is a chemical element; its chemical symbol is Au and atomic number 79. In its pure form, it is a bright-metallic-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transitio
Standard atomic weight
…186.21±0.01 1973 76 Os osmium 190.23±0.03 190.23±0.03 1991 77 Ir iridium 192.217±0.002 192.22±0.01 2017 78 Pt platinum 195.084±0.009 195.08±0.02 2005 79 Au gold 196.966570±0.000004 196.97±0.01 2017 80 Hg mercury 200.592±0.003 200.59±0.01 2011 81 Tl thallium [204.382, 204.385] 204.38±0.01 2009 82 Pb lead [206.14…
Gold crystals
A 5 mm (0.20 in) gold nugget (dot in front of frame) can be hammered into a gold foil of about 0.5 m2 (5.4 sq ft) in area.
Gold bars, also called ingots or bullion
Gold(III) chloride solution in water