silica

/'silikə/

Thân thiện

A scientist examines a sample of silica under bright laboratory lights.

Definition

1. Noun:
   • A hard, glassy mineral compound consisting of silicon and oxygen (SiO₂), occurring naturally in various forms such as quartz, cristobalite, and opal. It is a primary component of sand and many rocks.

Usage

• Silica is an uncountable noun used to refer to the compound silicon dioxide in general.
• It is commonly discussed in contexts of geology, chemistry, materials science, and industrial manufacturing.

Examples

• Noun:
  • The beach sand is primarily composed of silica.
  • Workers exposed to airborne silica dust may develop lung diseases.
  • This type of glass has a very high silica content.

Advanced Usage

• "Fumed silica" or "pyrogenic silica": A very fine, powdered form of silica produced by burning silicon tetrachloride in a flame of hydrogen and oxygen. It is used as a thickening agent and reinforcing filler.
  • Fumed silica is added to paints and coatings to prevent sagging.
• "Silica gel": A porous, granular form of silica used as a desiccant (drying agent).
  • The small packet of silica gel in the shoebox absorbs moisture.

Variants and Related Words

• Silicic (adjective): Relating to or containing silica or silicon.
  • Silicic acid is a general name for a family of chemical compounds containing silicon, oxygen, and hydrogen.
• Silicate (noun): A salt in which the anion contains both silicon and oxygen, especially one of the numerous insoluble often complex metal salts that constitute the majority of the earth's crust.
  • Minerals like feldspar and mica are common silicates.

Synonyms

• Silicon dioxide: The systematic chemical name for silica.
• Quartz: A specific, very common crystalline form of silica.

Related Phrases and Compounds

• Crystalline silica: The forms of silica with a regular, repeating atomic structure (e.g., quartz, cristobalite). This is the form most hazardous to health when inhaled as dust.
  • Occupational safety regulations limit exposure to crystalline silica.
• Amorphous silica: Silica without a regular crystalline structure (e.g., diatomaceous earth, silica gel). Generally considered less hazardous than crystalline forms.
  • Diatomaceous earth, a type of amorphous silica, is used in filters.

Học thuật

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

Từ đồng nghĩa

• silicon oxide
• silicon dioxide