Gold??????

Question

What is gold's family,origin of name, and who was it discovered by?

Answer 1

Gold
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This article is about the metal. For the color, see Gold (color). For other uses, see Gold (disambiguation).
79 platinum ← gold → mercury
Ag
↑
Au
↓
Rg
Periodic Table - Extended Periodic Table
General
Name, Symbol, Number gold, Au, 79
Chemical series transition metals
Group, Period, Block 11, 6, d
Appearance metallic yellow
Standard atomic weight 196.966569(4)  g·mol−1
Electron configuration [Xe] 4f14 5d10 6s1
Electrons per shell 2, 8, 18, 32, 18, 1
Physical properties
Phase solid
Density (near r.t.) 19.3  g·cm−3
Liquid density at m.p. 17.31  g·cm−3
Melting point 1337.33 K
(1064.18 °C, 1947.52 °F)
Boiling point 3129 K
(2856 °C, 5173 °F)
Heat of fusion 12.55  kJ·mol−1
Heat of vaporization 324  kJ·mol−1
Heat capacity (25 °C) 25.418  J·mol−1·K−1
Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 1646 1814 2021 2281 2620 3078
Atomic properties
Crystal structure cubic face centered
Oxidation states −1, 1, 2, 3, 4, 5
(amphoteric oxide)
Electronegativity 2.54 (Pauling scale)
Ionization energies 1st: 890.1 kJ/mol
2nd: 1980 kJ/mol
Atomic radius 135  pm
Atomic radius (calc.) 174  pm
Covalent radius 144  pm
Van der Waals radius 166 pm
Miscellaneous
Magnetic ordering diamagnetic
Electrical resistivity (20 °C) 22.14 n Ω·m
Thermal conductivity (300 K) 318  W·m−1·K−1
Thermal expansion (25 °C) 14.2  µm·m−1·K−1
Speed of sound (thin rod) (r.t.) (hard-drawn)
2030  m·s−1
Young's modulus 78  GPa
Shear modulus 27  GPa
Bulk modulus 220  GPa
Poisson ratio 0.44
Mohs hardness 2.5
Vickers hardness 216  MPa
Brinell hardness ? 2450  MPa
CAS registry number 7440-57-5
Selected isotopes
Main article: Isotopes of gold iso NA half-life DM DE (MeV) DP
195Au syn 186.10 d ε 0.227 195Pt
196Au syn 6.183 d ε 1.506 196Pt
β- 0.686 196Hg
197Au 100% Au is stable with 118 neutrons
198Au syn 2.69517 d β- 1.372 198Hg
199Au syn 3.169 d β- 0.453 199Hg
References

Gold (pronounced /ˈɡoʊld/) is a chemical element with the symbol Au (from the Latin aurum, meaning shining dawn) and atomic number 79. It is a highly sought-after precious metal which, for many centuries, has been used as money, a store of value and in jewelry. The metal occurs as nuggets or grains in rocks, underground "veins" and in alluvial deposits. It is one of the coinage metals. Gold is dense, soft, shiny and the most malleable and ductile of the known metals. Pure gold has a bright yellow color traditionally considered attractive.

Gold forms the basis for a monetary standard used by the International Monetary Fund (IMF) and the Bank for International Settlements (BIS). The ISO currency code of gold bullion is XAU. Modern industrial uses include dentistry and electronics, where gold has traditionally found use because of its good resistance to oxidative corrosion.

Chemically, gold is a trivalent and univalent transition metal. Gold does not react with most chemicals, but is attacked by chlorine, fluorine, aqua regia and cyanide. Gold dissolves in mercury, forming amalgam alloys, but does not react with it. Gold is insoluble in nitric acid, which will dissolve silver and base metals, and this is the basis of the gold refining technique known as "inquartation and parting". Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test," referring to a gold standard test for genuine value.
Contents

Answer 2

There are several colors of gold. White gold is mostly gold. It also has palladium and silver. Red gold has gold and copper. Yellow gold has gold, silver and copper. rose gold has the same materials but more copper and less silver than yellow gold. These are the types of gold used in watches. Jewelry may be grey, blue or green gold. White gold is not silver. It is much costlier.

Answer 3

Gold has been known since antiquity. Different languages have different names for it.

Answer 4

Gold's been known since antiquity, its symbol, Au, is reference to its Latin name - aurum, meaning "dawn".

Chemically, it's related to copper, silver and platnium.