The ore which contains copper and iron both is: (a) Cuprite (b) Chalcocite (c) Chalcopyrite (d) Malachite

When identifying copper ores, one must look at the distinctive chemical composition and physical characteristics associated with this metal. One common copper ore is cuprite, with a chemical formula of Cu₂O, where copper is in the +1 oxidation state. Another is chalcocite, Cu₂S, which is also a rich source of copper. Additionally, malachite, with a mineral composition of Cu₂(CO₃)(OH)₂, is easily recognized by its vibrant green coloring.

However, it is chalcopyrite, CuFeS₂, that is of particular interest as it contains both copper and iron, making it a primary source for extracting these metals. Chalcopyrite's brassy yellow color and metallic luster differentiate it from other copper ores. It is also distinguishable by its hardness and the greenish-black streak it leaves on porcelain. These traits are paramount to its identification process.

Iron is found in a multitude of ores alongside different elements. Ores like magnetite Fe₃O₄ and hematite Fe₂O₃ are prime sources of iron, dominantly extracting iron. However, there are ores which contain iron along with other commercial metals, such as chalcopyrite (CuFeS₂).

Chalcopyrite is particularly valuable because it contains copper as well as iron. Although not as rich in iron content as hematite or magnetite, chalcopyrite’s utility lies in the simultaneous extraction of copper. For students in courses like NEET Chemistry, understanding the color, streak, and appearance of such iron-containing ores can provide important clues to their identification and relevance to industry.

Preparing for competitive exams like the National Eligibility cum Entrance Test (NEET) demands a comprehensive understanding of chemistry topics, including the study of ores. It is essential for students to recognize various ores and their component metals. For example, knowing the composition of chalcopyrite, CuFeS₂, is critical as it might appear in NEET Chemistry multiple choice questions.

Students should focus on the appearance, composition, and applications of these ores in metallurgy. Additionally, mastering chemical reactions involved in the extraction and refining processes can be decisive in NEET success. Utilizing mnemonic devices can help in memorizing complex formulas, while regular practice with sample questions specifically on ores and metallurgy can build confidence and accuracy for the actual exam.