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https://en.wikipedia.org/wiki/Periodic_table
https://en.wikipedia.org/wiki/Group_11_element
https://en.wikipedia.org/wiki/Names_for_sets_of_chemical_elements
Group 11 is a group of chemical elements in the periodic table,
consisting of copper (Cu), silver (Ag), and gold (Au).
Roentgenium (Rg) is also placed in this group in the periodic table
Cu, 29:
Cuprum /k'ju pr.m/
Ag, 47:
Argentum /ar dzh'en t.m/
Au, 79:
Aurum /'> r.m/
Rg, 111:
Roentgenium /raent dzh'en i.m/
http://dictionary.reference.com/browse/roentgenium
https://en.wikipedia.org/wiki/Roentgenium
Roentgenium is a chemical element with symbol Rg and atomic number 111.
*It is an extremely radioactive synthetic element
(an element that can be created in a laboratory but is not found in nature);
roentgen /r'ae nt g.n/
倫琴（輻射的照射量單位）
//=== https://en.wikipedia.org/wiki/Periodic_table
2,8, 18,18, 32,32
