Silica is silicon dioxide
SiO2 is the chemical formula (not symbol) of silicon dioxide.
Silicon and oxygen..
Si02 is the chemical formula for silicon (Si) dioxide. It is major component to consumer and automotive glass, and used by the high tech industries for fabricating fiber optic cables.
The chemical compound silicon dioxide, also known as silica or silox (from the Latin "silex"), is an oxide of silicon, chemical formula SiO2, and has been known for its hardness since the 9th century[1]. Silica is most commonly found in nature as sand or quartz, as well as in the cell walls of diatoms. It is a principal component of most types of glass and substances such as concrete. Silica is the most abundant mineral in the earth's crust.
The answer that follows is good enough for personal knowledge or school students. Anyone higher than this should do read the Mantle page on wikipedia. Reference : NET The main element is oxygen. The main compound is silicon dioxide. (Si02)
Si02 plus h20 ---> h2Si03
covalent. it is a balenced molecule
A material that exists of only silicon and oxygen is called "Silica". Normally when found on it's own, silica is called Quartz. However, most volcanic minerals have some amount of silica in them.
65% sand (Si02) 13% sodium carbonate (Na2CO3) 12% limestone (CaCO3) 10% recycled glass but it varies slightly with different types of glass
Its made up of both. Oceanic crust is mostly mafic magma (basalt) and continental crust is mafic and felsic. The lithosphere also contains the upper portion of the upper mantle which is mostly mafic. The earths crust is 60% Si02 (silicates). Felsic rocks are much more silicate heavy than mafic. So one would assume that the crust is more felsic than mafic. That's just my conceptual thought process so don't take me on my word. Then again, the lithosphere also contains the upper mantle which is heavily mafic. So maybe the lithosphere in total is more mafic? Basically just typing thoughts down as they enter my brain. Answer I know for certain- Lithosphere is mafic and felsic.