Amorphous silica, SiO2, has a density of about 2.2 g/cm3, whereas the density of crystalline quartz, another form of SiO2, is 2.

Question

3 years ago

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Amorphous silica, SiO2, has a density of about 2.2 g/cm3, whereas the density of crystalline quartz, another form of SiO2, is 2.

65 g/cm3 . Which of the following statements is the best explanation for the difference in density
(a) Amorphous silica is a network-covalent solid, but quartz is metallic.
(b) Amorphous silica crystallizes in a primitive cubic lattice.
(c) Quartz is harder than amorphous silica.
(d) Quartz must have a larger unit cell than amorphous silica. (e) The atoms in amorphous silica do not pack as efficiently in three dimensions as compared to the atoms in quartz.

Chemistry

1 answer:

Y_Kistochka [10] · Answer 1 · 2022-09-04T11:36:06+03:00

Answer:

E. The atoms in amorphous silica do not pack as efficiently in three dimensions as compared to the atoms in quartz.

Explanation:

Quartz is a crystalline structure with a lattice which is very compact and produces flat faces that align with one another causing high density.

Silica has covalent bonding and forms a network structure. Silica, SiO2 is an amorphous solid and does not posses the same lattice or crystalline structure as Quartz, making it less dense.