Definition of physical and chemical properties of gold :
Gold is a metallic chemical symbol (Au),
one of the elements known since antiquity. It was possession of gold,
turquoise, yellow, bright and attractive sign of wealth for thousands
of years.
A shiny yellow metal in the form of blocks
can reflect the light seems Cefaiha tortillas green or blue. The gold
section Tkotaia accurate - is characterized by painted metal - while
there are other types of gold ranging in color from ruby and purple.
The gold in the transition team No. 1
the periodic table of chemical elements, and atomic number (79), and
mass Agency (196.967), and melt gold at a temperature of (1064) degrees
Celsius, and boils at (2856) degrees Celsius, and gold a good conductor
of heat and electricity.
The pure gold of the most viable types
of metal for roads and clouds, where you can hit him or his ways, even
up to the intensity (0.000013) cm. Can also form a golden wire length
(100) km from the amount of $ (29) grams. Gold and one of the most
metal soft bodied, with a hardness of (2.5) to (3) on a scale of hardness.
And gold of a very noble metal is not affected
by air or heat or humidity. And dissolves in concentrated
mineral acids known, such as hydrochloric acid,
and sulfuric,
phosphoric, and nitric acid but dissolves in
aqua regia a mixture of
hydrochloric and nitric acid centers.
The importance of gold:
He knew the gold and its value has emerged
since ancient times, easily formed metal more than any other metal.
In addition to the easy availability of gold in its pure form. The
beauty of gold and luster, and resistance to corrosion of metals has made
him outstanding in the various arts and crafts since ancient times.
Given the relative rarity of gold has been used as currency and the
basis for international.
