Sodium silicate (Na₂SiO₃) is an inorganic salt composed of silicon dioxide (SiO₂) and sodium oxide (Na₂O). It commonly appears as colorless crystals or white powder and is easily soluble in water, forming a viscous solution (commonly known as "water glass"). Its core properties include:
1. Alkalinity: The pH of a 10% aqueous solution is as high as 12-13 (source: Handbook of Inorganic Chemistry), so direct skin contact should be avoided.
2. Adhesiveness: The solution forms a silica gel layer upon drying and is widely used as an adhesive.
3. High-temperature resistance: The melting point is approximately 1088°C (according to the American Chemical Society), making it suitable for use in refractory materials.