Making Silicon Looking into Compounds and Making Silica

The video tutorial discusses silicon dioxide, focusing on its polymorphic nature, which allows it to exist in both crystalline and amorphous forms. Quartz is highlighted as a crystalline form, while minerals like Jasper and Onyx are amorphous. Keselgar, another amorphous form, is derived from diatoms. The preparation of silicon dioxide through the oxidation of silicon and heating of orthosilicic acid is also explained.

What is polymorphism in the context of silica?

• The ability to dissolve in water

• The ability to exist in different forms

• The ability to change color

• The ability to conduct electricity

Which of the following is a crystalline form of silica?

• Jasper

• Onyx

• Quartz

• Keselgar

What are diatoms in relation to silica?

• A form of silicon dioxide

• A chemical used to produce silica

• A source of amorphous silica

• A type of crystalline silica

How is silicon dioxide prepared from orthosilicic acid?

• By cooling it to low temperatures

• By exposing it to sunlight

• By mixing it with water

• By heating it to around 900°C

What is the chemical formula for silicon dioxide?

• Si2O2

• Si2O

• SiO2

• SiO