Problem 32 - A Complete Resource Book in Chemistry for JEE Main

Question

The ore which contains copper and iron both is (a) cuprite (b) chalcocite (c) chalcopyrite (d) malachite

Step-by-Step Solution

Answer

The ore is chalcopyrite.

Step 1: Understanding the Question

The question asks for the identification of an ore that contains both copper and iron. We are given four options: cuprite, chalcocite, chalcopyrite, and malachite.

Step 2: Analyzing Each Ore

1. Cuprite is a copper oxide mineral and does not contain iron. 2. Chalcocite is a copper sulfide mineral and also lacks iron. 3. Chalcopyrite is a mineral known to contain both copper and iron. Its chemical formula is CuFeS₂. 4. Malachite is a copper carbonate mineral and does not contain iron.

Step 3: Identifying the Ore

From the analysis, chalcopyrite is the only ore that contains both copper and iron, while the others contain only copper along with other elements.

Step 4: Conclusion

Based on the chemical composition of the ores analyzed, the correct answer is chalcopyrite as it contains Cu (copper) and Fe (iron).

Key Concepts

copper ore

Copper ore is a type of mineral rich in copper, a valuable metal used in various applications. These ores can be found naturally in the earth and are usually extracted through mining. Copper is crucial for electrical conductivity, making it important for wiring and electronics. In nature, copper can bond with different elements producing various types of ores. Some common copper ores include:

• Chalcopyrite: Contains both copper and iron.
• Cuprite: Mainly consists of copper and oxygen.
• Chalcocite: Predominantly copper and sulfur.
• Malachite: Another copper ore coupled with carbonates.

Mining and refining processes can extract pure copper from these ores, which has countless uses in industry and construction. Understanding the different types of copper ores is essential in identifying the sources and the potential applications of copper.

iron ore

Iron ore is another important type of mineral. Unlike copper, iron is a basic component used for building structures and manufacturing machinery. Iron ores contain iron compounds from which pure iron can be extracted. The well-known forms of iron ores include:

• Hematite: Consisting mainly of iron and oxygen.
• Magnetite: Combining iron and oxygen in a different ratio.
• Taconite: A low-grade iron ore variably mixed with silicates.

Iron's versatile properties such as strength and durability have historically made it a material of choice for tools and infrastructure. An ore, like chalcopyrite, containing both iron and copper, is unique as it allows retrieval of both metals from a single source, making it both efficient and valuable.

mineral composition

The composition of minerals refers to the elements and compounds that make up a particular mineral. Understanding mineral composition is fundamental in geology and mining because it determines the mineral's properties and uses. The mineral composition can be influenced by several factors such as the environment of formation and the chemical reactions involved. Chalcopyrite, for example, is composed of copper, iron, and sulfur, giving it distinct properties:

• It has a bright, metallic luster.
• It is usually a brass-yellow color.
• It has a hardness of 3.5 to 4 on the Mohs scale.

Knowing these properties helps in identifying and processing the mineral effectively. The identification of minerals with particular compositions allows industries to determine their usage for technological or structural applications.

chemical formula CuFeS₂

The chemical formula CuFeS₂ represents chalcopyrite, a mineral consisting of copper, iron, and sulfur. This formula is a shorthand way of expressing the proportions and types of atoms present in chalcopyrite. Each element contributes specific characteristics to the mineral:

• Copper (Cu) imparts electrical conductivity, essential for many industrial applications.
• Iron (Fe) provides structural strength, making it valuable in construction and manufacturing.
• Sulfur (S) influences the ore's overall mineral structure and behavior.

The composition represented by CuFeS₂ signifies chalcopyrite's dual importance as a source for both copper and iron. This makes it a densely packed mineral in terms of utility, being simultaneously harnessed for its multiple constituent elements in various industries.