Which of the following is not an ore of iron?A. HaematiteB. LimoniteC. CassiteriteD. Magnetite

To determine which of the given options is not an ore of iron, let’s briefly look at each one:

A. Haematite
Chemical Formula: Fe₂O₃
Description: This is one of the most important ores of iron, containing a high percentage of iron (about 70%).
Usage: It is extensively used in the production of iron and steel.
B. Limonite
Chemical Formula: Generally represented as FeO(OH)·nH₂O
Description: Limonite is an iron ore composed of a mixture of hydrated iron(III) oxide and iron(III) hydroxide.
Usage: It is another significant source of iron.
C. Cassiterite
Chemical Formula: SnO₂
Description: Cassiterite is an ore of tin, not iron. It does not contain iron and is primarily used to extract tin.
Usage: The main source of tin for various applications, including solder and alloys.
D. Magnetite
Chemical Formula: Fe₃O₄
Description: Magnetite is another important iron ore with a high iron content (about 72%).
Usage: Widely used in the iron and steel industry.
Conclusion
From the analysis, C. Cassiterite is not an ore of iron; it is an ore of tin. Thus, the correct answer is C.