Page 5 - Curriculum Visions Dynamic Book

Not surprisingly, perhaps, among this huge variety of substances, most of which are good for our way of living,
there will be some that cause concern. Carbon-containing compounds called CFCs have been responsible for
destroying part of the world’s protective ozone layer. Other compounds, such as the pesticide DDT, may
be life-threatening if humans and animals are exposed to large doses. Historically, as scientists
tried to classify the bewildering array of carbon- based compounds, they made an important
distinction between those they called organic compounds, and those called inorganic
compounds. Limestone rock (calcium carbonate) and carbon gases (such as carbon dioxide and carbon monoxide) are
part of the group called inorganic chemicals. Chemicals like those based on petroleum,
which
are formed from living tissue, are by
far the most numerous and are called organic chemicals.
Because carbon compounds so
greatly outnumber those made of any other
element, it would be impossible
to include examples of the majority of the
compounds and their properties. Rather, this book will describe the main categories
of carbon compounds and a few of the most common compounds.
 This is silicon carbide, a compound of silicon and carbon, SiC, whose crystals form black, glossy plates. It is an extremely hard mineral and known by the common name of carborundum. When ground down into a grit, carborundum makes an abrasive that is widely used in industry.
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