hilary duff

                             
                                            GOLD
Gold (play / ɡoʊld /) is a chemical element with symbol Au (from Latin: Aurum "gold") and the atomic number of 79 Gold is dense, soft, shiny metal, and the most malleable and ductile metal known. [Edit] Pure gold is bright yellow in color and luster has traditionally been regarded as attractive, which has no oxidizing in air or water. Chemically, gold is a transition metal and Group 11 elements. And 'one of the least reactive solids. The metal is then often the element-free (native) format, such as nuggets or grains in rocks, in veins and alluvial deposits. Less frequently occurs in minerals such as gold compounds, usually in tellurium.

Gold is resistant to acid attacks individuals, but can be dissolved by the royal (nitro-hydrochloric acid), so called because it dissolves gold. Gold dissolves in cyanide alkaline solutions, which were used in the mining industry. Gold dissolves in mercury, forming amalgam. Gold is insoluble in nitric acid, which dissolves metals and silver, a property that has been used to confirm the presence of gold in the elements, giving rise to the term of the event.

Gold was a highly sought after precious metal for precious pieces, jewelry and other art forms since before the beginning of history. Gold standards are the basis for the most common monetary policy throughout human history, largely supplanted by fiat currency only in the late 20th century. Gold is also often associated with a wide range of symbolism and ideology. A total of 165 000 tonnes of gold was mined in human history, as in 2009. This corresponds to approximately 5.3 billion troy ounces, or in terms of quantity, about 8500 m3, a cube 20.4 m on one side. Global consumption of new gold production is around 50% in jewelry, 40% and 10% of investments in industry .

In addition to the extended functionality monetary and symbolic, yet many practical applications in dentistry, electronics and other fields. The high formability, hardness, corrosion resistance and most other chemical reactions, and the conductivity of electricity has led to many uses of gold, including the son, the production of colored glass, and eating leaves gold itself.