EARTH SCIENCE
MINERALOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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isolated structure, chain structure, framework structure
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framework structure, isolated structure, sheet structure
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framework structure, chain structure, isolated structure
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sheet structure, framework structure, chain structure
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Detailed explanation-1: -Electrons are shared in a covalent bond. Silicon and oxygen bond together to create a silica tetrahedron (a pyramid shape with O at each corner and Si in the middle – see figure to the left and [Figure 2.21]), which is the building block of the many different silicate minerals.
Detailed explanation-2: -In quartz (SiO2), the silica tetrahedra are bonded in a “perfect” three-dimensional framework.
Detailed explanation-3: -Quartz. Quartz (SiO2; Figure 5.29) contains only silica tetrahedra. In quartz, each silica tetrahedron is bonded to four other tetrahedra (with an oxygen shared at every corner of each tetrahedron), making a three-dimensional framework. As a result, the ratio of silicon to oxygen is 1:2.
Detailed explanation-4: -The silicon tetrahedron: Silicon (Si+4) is typically surrounded by four oxygen atoms (O-2) to form a stable silicon tetrahedron (SiO4). This geometric structure is very strong, because the tiny silica atom nestles perfectly between four large oxygens, covalently bonded to each.