Definition

1. Noun:
   • A jellylike substance (hydrated silica): "Silicic acid" refers to a chemical compound, a hydrated form of silica, which often appears as a gelatinous, amorphous solid. It is a weak acid and a precursor to many silicate minerals and materials.

Usage Examples

• Noun:
  • Silicic acid is formed when sodium silicate reacts with an acid.
  • The gel used in some chromatography columns contains silicic acid.
  • Researchers studied the polymerization of silicic acid in solution.

Advanced Usage

• In Chemistry and Geology: The term is used to describe the various forms of silica in aqueous systems, often represented by the formula SiO₂·nH₂O. It is central to understanding the biogeochemical cycling of silicon and the formation of siliceous sediments.
  • The dissolution of quartz contributes to the concentration of silicic acid in natural waters.

Variants and Related Words

• Silica (n): Silicon dioxide (SiO₂), a hard, unreactive, colorless compound that occurs as quartz and in sandstone and many other rocks. It is the anhydrous form related to silicic acid.
• Silicate (n): A salt in which the anion contains both silicon and oxygen, especially one of the anion SiO₄²⁻. Silicates are derived from silicic acids.
• Orthosilicic acid (n): The simplest silicic acid, Si(OH)₄, often referred to in discussions of soluble silicon in biology.

Synonyms

• Hydrated silica
• Polymeric silicic acid (for its polymerized forms)

Notes on Usage

• The term "silicic acid" is often used in a general sense for a range of compounds and polymeric forms, not a single well-defined molecule. In many contexts, it refers to the soluble, reactive forms of silica in water.
• It is primarily a technical term used in scientific fields (chemistry, geology, materials science, environmental science) and is uncommon in everyday conversation.

Noun

1. a jellylike substance (hydrated silica)