Question

Ordinary glass is a mixture of:
A. Sodium silicate, calcium silicate
B. sodium silicate, calcium silicate and silica
C. sodium silicate and silica
D. none of the above

Answer 1

Hint: Ordinary glass is a solid formed by rapid melt quenching. An alternate definition of glass is that it is any non-crystalline (amorphous) solid that exhibits a glass transition when heated towards the liquid state. Due to the chemical bonding constraints, glasses do possess a high degree of short-range order with respect to local atomic polyhedra.

Complete step by step answer:
Silicon dioxide (\[Si{O_2}\] ) is a common fundamental constituent of glass. Glass consists of various silicates that have a $Si - O - Si$ covalent bonding in them and form a long chain, ring or caged structures which provide stiffness and crystalline form to the glass. Fused quartz is a glass made from chemically-pure silica and does not have any kind of impurities in it. It has very low thermal expansion and excellent resistance to thermal shock, being able to survive immersion in water while red hot, resists high temperatures and chemical weathering, and is very hard. It is also transparent to a wider spectral range than ordinary glass, extending from the visible further into both the UV and IR ranges, and is sometimes used where transparency to these wavelengths is necessary. Thus, we can simply say that silicates of sodium, calcium and various other metals along with the silica itself are the constituent components of ordinary glass.

Thus, the correct option is B .

Note:
Fused quartz or simply a form of ordinary glass is used for high-temperature applications such as furnace tubes, lighting tubes, melting crucibles, etc. However, its high melting temperature and viscosity make it difficult to work with. Therefore, normally, other substances are added to lower the melting temperature and simplify glass processing.