A clip of a classmate cleaning glass.

The clip describing students cleaning glass is as follows:

After school, a group of lovely children are carefully cleaning in the bright classroom. Some of them clean the glass, some clean the table, some sweep the floor and some sprinkle water. The children who cleaned the glass polished the glass like a big mirror.

Glass is introduced as follows:

Glass is an amorphous inorganic nonmetallic material, which is generally made of various inorganic minerals (such as quartz sand, borax, boric acid, barite, barium carbonate, limestone, feldspar, soda ash, etc.). ) as the main raw material, and add a small amount of auxiliary raw materials.

Its main components are silicon dioxide and other oxides. The chemical composition of ordinary glass is Na2SiO3, CaSiO3, SiO2 or Na2O CaO 6SiO2, etc. The main component is silicate double salt, which is an amorphous solid with irregular structure.

Widely used in buildings, used for wind and shading, belonging to a mixture. In addition, colored glass doped with oxides or salts of certain metals shows color, and tempered glass made by physical or chemical methods. Some transparent plastics, such as polymethyl methacrylate, are sometimes called plexiglass.

The development of glass is introduced as follows:

The earliest glass manufacturer in the world was the ancient Egyptians. The appearance and use of glass has a history of more than 4000 years in human life. Small glass beads have been unearthed from the remains of Mesopotamia and ancient Egypt 4000 years ago.

/kloc-in the 0/2 century, commercial glass appeared and began to become an industrial material. /kloc-in the 0/8th century, in order to meet the needs of making telescopes, optical glass was made. 1874, Belgium made flat glass for the first time.

The application of glass is introduced as follows:

Timely glass, silicate glass, soda-lime glass, fluoride glass, high-temperature glass, high-pressure glass, ultraviolet-proof glass and explosion-proof glass.

Usually refers to silicate glass, which is made of quartz sand, soda ash, feldspar and limestone through mixing, high-temperature melting, homogenization, processing and molding, and then annealing. Widely used in construction, daily use, art, medical care, chemistry, electronics, instrumentation, nuclear engineering and other fields.