الذهب
Gold is a metal of wealth and money, and it is a chemical element symbolized by the two letters Au, in relation to its name in Latin, and people use it as a monetary unit, and it is found in nature in the form of shiny granules inside rocks, or in the bottoms of rivers, and in the form of veins in the ground, and it has been discovered The largest nugget of gold in Australia in 1896 AD, weighing 2.280 ounces.
The process of purifying gold takes place by separating dust, silt, and impurities from it by means of strong water currents, where sand and silt are removed from it, which keeps gold particles in their places, or mercury may be used to dissolve gold without sand and impurities, then the gold is purified from mercury by the process of mercury distillation .
Properties of gold
Gold is distinguished from other metals by many physical and chemical properties, due to its chemical nature, as it carries the atomic number (79) and the atomic mass (196.967). Among its most important properties are the following:
- Gold is soft.
- Shiny.
- Less corrosion.
- high density.
- It is a good conductor of electricity.
- It is a good conductor of heat.
- ductility, malleability, and formability.
- The melting point of gold is one thousand sixty-four degrees Celsius.
- The boiling point of gold is two thousand eight hundred and fifty six percent.
- Being inert, gold does not react with air, water, heat, or moisture.
- It dissolves in aqua regia, which is a mixture of hydrochloric and nitric acid.
- It is dissolved in a solution of sodium thiosulfate with oxygen.
- It dissolves in solutions of cyanide and alkaline elements.
uses of gold
The availability of gold among the pharaohs led to its use in making coffins of kings and some tools such as chariots, and they also used a mixture of gold with some cosmetic ointments to make masks for the skin as they made Tutankhamun’s mask, but these days gold is the origin of the monetary material used by the International Monetary Fund and the Bank for Settlements International, and gold has other uses in:
Read also:What did the Arabs call gold?- The field of dentistry, such as crowning and filling teeth.
- Jewelry and ornamental industry.
- Treatment of rheumatism and bone infections; Where the so-called gold solution is manufactured.
- treatment of some types of cancer; Where radioactive gold No. (198) is used.
- Medicine packaging.
- Electronics industry, microelectronic circuits.
whereabouts of gold
Gold is found in nature in two states: either as primary deposits, or in riverine gatherings as transported deposits, and these are the most important global regions rich in this shiny metal:
Read also:What is the source of diamond minerals?- Nevada.
- Alaska.
- California.
- Urals.
- South Dakota.
- Province of Ontario, Canada.
- The rand region in the Transvaal in the Union of South Africa, which produces nearly forty percent of world gold production.
