Definition

Noun: 1. A chemical compound: A white or colorless, vitreous (glass-like), and generally insoluble solid with the chemical formula SiO₂. It is the primary constituent of most sand and many rocks, occurring widely in the earth's crust in several crystalline and amorphous forms.

Examples of Usage

• Noun:
  • Quartz is a common crystalline form of silicon dioxide.
  • The high purity of the silicon dioxide is crucial for manufacturing optical fibers.
  • Sand, which is largely composed of silicon dioxide, is a key ingredient in making glass.

Advanced Usage

• In Geology and Materials Science: The term is used to specify the specific chemical composition of a mineral or material, distinguishing it from other compounds.
  • The analysis confirmed the layer was pure silicon dioxide, not a silicate.
• In Industry: Often referred to by its common names (e.g., silica, quartz) depending on the form and application.
  • Fumed silicon dioxide is used as a thickening agent in paints and cosmetics.

Variants and Related Words

• Silica (n): A common synonym for silicon dioxide, especially when referring to its various impure or industrial forms.
  • Diatomaceous earth is a natural source of amorphous silica.
• Quartz (n): The most common and stable crystalline form of silicon dioxide at the Earth's surface.
• Cristobalite / Tridymite (n): Other, less common crystalline polymorphs of silicon dioxide.
• Lechatelierite (n): A natural silica glass, an amorphous form of silicon dioxide, formed by lightning strikes or meteorite impacts.

Synonyms

• Silica
• SiO₂ (the chemical formula)

Related Phrases / Terms

• Fused silica: A glass made from high-purity silicon dioxide.
• Silica gel: A porous, granular form of silicon dioxide used as a desiccant (drying agent).
• Silicosis: A lung disease caused by inhaling crystalline silicon dioxide dust.

Noun

1. a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite