MCQ Detailed View

Cassiterite is the principal ore of tin (Sn) and is chemically known as tin dioxide (SnO₂). It is a hard, dense, and usually brown or black mineral found in igneous and alluvial deposits. Cassiterite is highly stable and resistant to weathering, making it a reliable source of tin.

Tin is extracted from cassiterite through a process called reduction. The ore is first concentrated by gravity separation to remove impurities. Then, the purified SnO₂ is reduced with carbon in a furnace, producing metallic tin:

SnO₂ + C → Sn + CO₂

Cassiterite is mined extensively in countries like China, Indonesia, Peru, and Bolivia, where it is found in primary deposits (veins in rocks) or secondary alluvial deposits formed by the weathering of rocks.

Other options like manganese (Mn), nickel (Ni), and antimony (Sb) come from their respective ores: pyrolusite (MnO₂) for manganese, pentlandite ((Ni,Fe)₉S₈) for nickel, and stibnite (Sb₂S₃) for antimony. Cassiterite specifically provides tin, which is widely used in soldering, plating, alloys (like bronze), and tin containers.

Understanding cassiterite as the main tin ore is essential in inorganic chemistry and industrial applications. It also helps students differentiate between various metal ores, recognize chemical formulas, and learn extraction techniques. Cassiterite is not only economically important but also a classic example of an ore in metal extraction studies.