what is a silicate?
In chemistry, it is any member of a family of anions consisting of silicon and oxygen.
Silicate
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula , where . 
what is the diameter of earth in km UNANSWERABLE what is the axial tilt of the planet? Approximately 23.439281° describe the internal structure of it? It is divided into layers by their chemical or physical (rheological) properties. For eg. the outer layer is a chemically distinct silicate solid crust.
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Silicate [SEP] Introduction
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is also used for any salt of such anions, such as sodium metasilicate; or any ester containing the corresponding chemical group, such as tetramethyl orthosilicate. Silicate anions are often large polymeric molecules with an extense variety of structures, including chains and rings (as in polymeric metasilicate ), double chains (as in , and sheets (as in . In geology and astronomy, the term silicate is used to mean silicate minerals, ionic solids with silicate anions; as well as rock types that consist predominantly of such minerals.