Chemistry Element: Gold
Neutrons
118
number of neutrons
118
year of discovery
1848
Atomic mass
196
Atomic Number
79
Electrons
79
Protons
79
number of electrons
79
number of protons
79
Gold fact #3
A single ounce of gold (about 28 grams) can be stretched into a gold thread 5 miles (8 kilometers) long. Gold threads can even be used as embroidery thread.
Solid
At room temperature gold is a solid. Pure gold melts at 1943 degrees F (1062 degree C).
Symbol
Au
Block
D
weight of the gold
Gold has a high unit weight. Gold's unit weight is 315.2 g/cu inch (19.3 g/cu cm). Gold is therefore about 19 times heavier than the same amount of water and 3 times heavier than iron. This property of gold makes it possible for people to find gold by "panning for gold". Gold prospectors place sand and gravel in a pan and wash and swirl water around so all the gold sinks to the bottom because it is heavier.
Gold fact #1
Gold is the only metal that is yellow or "golden". Other metals may develop a yellowish color, but only after they have oxidized or reacted with other chemicals.
Location
Group 11, Period 6
Discovery
It has known since prehistoric times. In 2,000 B.C. the Egyptians began Gold mining.
How is gold
It is possible to cut gold with a knife. Gold is also the most ductile of all metals. It is possible to press gold into a foil with a thickness of less than 5 millionths of an inch (0.12 millionths of a meter). It is also possible to flatten one ounce (28.3 grams) of gold into a sheet 100 square feet (9.3 square meters) in size or a wire nearly 1 mile (1.6 km) long
Major Uses
Jewelries, Coins, Trophies
Gold fact #2
Nearly all of the gold on Earth came from meteorites that bombarded the planet over 200 million years after it formed.
Appearance
Soft, yellow-orange metal
Phase
Solid
Gold Rush
The 1800's brought many gold discoveries around the world. In 1848, a man named James Marshall found gold in California near the Sierra Nevada Mountains. This was the start of the California gold rush. In 1851 gold was discovered in Australia. In 1886 gold was discovered in South Africa, leading to the start of a war between the British and Boers (Dutch settlers). In 1896 gold was discovered in the Yukon, which is now Alaska (50th U.S. State).
Discoverer
Unknown
The world's largest gold nugget
found was over 5 feet tall found in Hill End, Australia in 1872. It weighed 204 lbs (93kg).
How is gold measured
in karats. A karat is a measure of the pure gold in a gold alloy. 24 karat gold is pure gold. 14 karat gold is 58.3 percent pure gold. 18 karat gold is 75 percent per gold.
period
iron
Elements compound
silver, copper,zinc and nickel
Gold today
the leading gold mine locations are South Africa, Russia, the United States, Canada, Australia, Brazil and China. The Transvaal Province of South Africa (near Johannesburg) produces over a quarter of the world's annual gold production