Chemical formula of Quartz is?

The correct answer is SiO₂. Quartz is a hard, crystalline mineral composed entirely of silicon dioxide (SiO₂). It is the second most abundant mineral in Earth's continental crust, after feldspar.

Quartz and Common Mineral Formulas

• SiO₂ – Silicon Dioxide: Each silicon atom is covalently bonded to four oxygen atoms, forming a tetrahedral structure that links to create a continuous three-dimensional framework. This gives quartz its hardness (7 on the Mohs scale) and resistance to chemical weathering.
• CaCO₃ – Calcium Carbonate: This is the chemical formula of calcite, the main constituent of limestone and marble. It is not quartz.
• Al₂O₃ – Aluminium Oxide: This is corundum, the mineral that forms ruby and sapphire. It is extremely hard but distinct from quartz.
• Fe₂O₃ – Iron(III) Oxide: Commonly known as hematite, an iron ore. It gives a reddish streak and is often responsible for the red color of many rocks.

Thus, the chemical formula of quartz is SiO₂.