Question
Question: Basic unit of Zeolite, mica, asbestos and feldspar is: (A) \(Si{{O}_{4}}^{-4}\) (B) \(Si{{O}_{2...
Basic unit of Zeolite, mica, asbestos and feldspar is:
(A) SiO4−4
(B) SiO2
(C) SiO32−
(D)
Solution
Silicate minerals are the most common of Earth's minerals and include quartz, feldspar, mica, amphibole, pyroxene, and olivine. Silica tetrahedral, made up of silicon and oxygen, form chains, sheets, and frameworks, and bond with other cations to form silicate minerals.
Complete step by step answer: Zeolites are crystalline solids structures made of silicon, aluminum and oxygen that form a framework with cavities and channels inside where cations, water and/or small molecules may reside. They are often also referred to as molecular sieves. Zeolites are the aluminosilicate AlO45− and SiO44− ) members of the family of microporous solids known as "molecular sieves", and mainly consist of Si, Al, O, and metals including Ti, Sn, Zn, and so on. Mica is a mineral name given to a group of minerals that are physically and chemically similar. They are all silicate minerals, known as sheet silicates because they form in distinct layers. -Asbestos is a term used to refer to six naturally occurring silicate minerals. All are composed of long and thin fibrous crystals, each fibre being composed of many microscopic 'fibrils' that can be released into the atmosphere by abrasion and other processes.
-Feldspars KAlSi3O8 –NaAlSi3O8 –CaAl2Si2O8 are a group of rock-forming tectosilicate minerals that make up about 41% of the Earth's continental crust by weight. Feldspars crystallize from magma as both intrusive and extrusive igneous rocks and are also present in many types of metamorphic rock.
All these are silica minerals with basic unit SiO4−4.
Hence, the correct answer is A option.
Note: Asbestos is an excellent electrical insulator and is highly heat-resistant, so for many years it was used as a building material. Micas are fairly light and relatively soft, and the sheets and flakes of mica are flexible.