Silicon Dioxide Chemical Properties

PPT 4.5 Physical Properties in Giant Covalent Substances PowerPoint


Silicon dioxide, also known as silica, is a chemical compound that is abundantly present in the Earth’s crust. It is a naturally occurring mineral and is found in various forms such as quartz, sand, and clay. Silicon dioxide is widely used in various industries due to its unique chemical properties.

Chemical Composition

Silicon dioxide is composed of two elements, silicon and oxygen. Its chemical formula is SiO2. It has a molecular weight of 60.08 g/mol and a melting point of 1713°C.

Physical Properties

Silicon dioxide is a hard and brittle material with a density of 2.65 g/cm³. It is insoluble in water and most organic solvents. It has a high melting and boiling point, making it suitable for use in high-temperature applications.

Chemical Properties

Silicon dioxide is a highly stable compound and is resistant to most chemical reactions. It is not affected by acids, except for hydrofluoric acid. When heated with alkaline substances, it forms silicates.


Silicon dioxide has numerous industrial applications. It is used as a filler in rubber and plastics, as a reinforcing agent in concrete, and as an abrasive in toothpaste and other products. It is also used in the production of glass, ceramics, and semiconductors.

Health Effects

Silicon dioxide is generally considered safe for human consumption. However, inhalation of silica dust can cause lung damage and lead to the development of lung cancer. It is important to handle and use silicon dioxide in a safe and responsible manner.

Environmental Impact

Silicon dioxide is a naturally occurring compound and is not considered harmful to the environment. However, the mining and processing of silica can have negative impacts on the environment, including soil erosion and water pollution. It is important to implement sustainable practices in the mining and processing of silica.


Silicon dioxide is a versatile compound with unique chemical properties. It has numerous industrial applications and is widely used in various industries. It is important to handle and use silicon dioxide in a safe and responsible manner to minimize its impact on human health and the environment.