Gold was one of the first elements known to man. This is because it occurs in nature in the form of the solid metal and sometimes in very large pieces. Pure gold cannot be made in nature. The gold that is mined is an alloy that has other metals in it as well. The other metals can be taken out by a couple of different ways, including just melting down the mixture, or when it is in its liquid state blasting it with air, which turns the non-gold particles into a compound that is not soluble in metal, and can therefor just be taken off the top of the liquid gold. Gold is a very functional metal. Because, like all metals, its atoms can be reformed while still remaining close to each other, gold can be turned into wire or smashed out into sheets. The thin sheets of gold are used for decoration, both edible and non-edible, as well as for more practical purposes such as coating windows to either reflect or keep in heat. The gold used in jewelry is actually an alloy, mixed with silver, copper, and nickle. This is done because pure gold is very soft and mixing it with those other metals makes it strong enough to stand up to daily wear and tear. The amount of gold in an alloy is measured using carats. 24 carat gold is 100% pure gold. To get the carats of gold you divide the mass of gold in the sample by the mass of the whole sample and multiply that number by 24. (ex. (20/32) X 24= 15 carats)
Alloy-a mixture of metals
Compound-a material that consists of two or more types of atomsin a fixed ratio, with uniform composition throughout, and that connot be easily separated into its pure component elements.
Carat- gold-alloy classification system; carats of gold = 24 X fraction of mass that is pure gold
It was interesting to read on some of the more practical uses of gold. As far as I knew it was used almost purly for decoration. The bit about using it to coat windows was something completely new to me. It was also nice to learn exactly how the carat system works. Potentially lead to further investigation of the properties of gold and therefore potentially more uses for the element.
Baird, Colin "Chemistry in You Life" second edition. New York: W.H. Freeman and Company, 2006. 24-26, G-1, G-2, G-3
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