Different forms of silica such as quartz tridymite and
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Different forms of silica such as quartz, tridymite and cristobalite are as follows:
Quartz 870∘C⟶ Tridymite 1470∘C⇌ Cristobalite
(SiO2) (SiO2) (SiO2)
The structure possessed in them is:
A.
Sheet silicate
B.
Three-dimensional silicate
C.
Chain silicate
D.
Cyclic or ring silicate
Please scroll down to see the correct answer and solution guide.
Right Answer is: B
SOLUTION
Three-dimensional sheet silicates or framework minerals: Complete sharing of all four oxygen atoms in all tetrahedral gives a three-dimensional network. The empirical formula for such a substance would be (SiO2)n, i.e. we would have silica. This type of structure is characteristic of three forms of silica, i.e. quarts, tridymite and crystallobalite.