Element Profile: Gold

Gold is a chemical element with the symbol Au and atomic number 79. Its standard
relative atomic mass is 196.967.

In the periodic table, gold sits in group 11 and period 6, and it belongs to the
d block. It is classified as a transition metal. Its ground-state electron
configuration is [Xe] 4f14 5d10 6s1.

Physically, gold melts at 1064.18 °C and boils at 2836 °C. Its density at room
temperature is 19.3 g/cm³, and at 20 °C it is a solid. The non-bonded atomic
radius of gold is 2.14 Å.

Chemically, gold exhibits oxidation states of 5, 4, 3, 2, 1, -1, with +3 being
the most common. Its electronegativity on the Pauling scale is 2.4.

Gold has been known since ancient times; it was discovered approximately 3000 BC,
and its discoverer is Unknown. The CAS registry number for gold is 7440-57-5.

A soft, yellow metal, gold is commonly used in jewelry, coinage, electroplating,
dental work, industrial catalyst.
