Test: Metallurgy - SSC CGL MCQ

Metallurgy is the science and art of extracting metals from their ores. This process involves various steps such as concentration of the ore, extraction of the metal, and refining of the metal. It plays a crucial role in obtaining pure metals from their naturally occurring mineral forms, thereby enabling the production of various useful materials and products.

Ores are minerals from which metals can be extracted conveniently and profitably. Not all minerals are ores; only specific minerals contain a high enough concentration of the desired metal to make extraction economically viable. Gangue, on the other hand, refers to the impurities associated with the ore and is separated during the extraction process.

Bauxite is an ore from which aluminium is extracted. The primary component of bauxite is aluminum oxide (Al2O3), which is processed to obtain pure aluminium metal. Aluminium is a widely used metal in various industries due to its lightweight, corrosion-resistant properties.

Pyrolusite is an ore from which manganese is extracted. Manganese is a key element in steelmaking and is used in the production of batteries, fertilizers, and various other industrial applications. The extraction of manganese from pyrolusite involves several metallurgical processes to obtain the pure metal.

The concentration of the ore is a crucial step in the extraction process that involves separating the valuable mineral from the gangue or unwanted materials. This process helps in removing impurities and increasing the concentration of the desired metal, making the subsequent extraction process more efficient and cost-effective.

Metallurgy is primarily focused on extracting metals from their ores. This process involves several steps such as concentration of the ore, extraction of the metal, and refining of the metal. By extracting metals from ores, metallurgy plays a crucial role in obtaining pure metals that can be used for various industrial purposes.

- Asbestos:
- Not considered an ore.
- It is a fibrous mineral used mainly for insulation and fireproofing.
- Does not contain extractable metal or economic minerals.

- Gypsum:
- Considered an ore.
- Mined for its use in drywall and plaster.

- Limestone:
- Considered an ore.
- Used in cement and lime production.

- Rocksalt:
- Considered an ore.
- Mined for sodium chloride (table salt).

Asbestos is used for its physical properties, not for extracting metals or minerals.

Gangue, also known as matrix, refers to the impurities associated with the ore. In metallurgy, the purpose of gangue is to be separated from the valuable minerals or ores during the extraction process. Removing gangue helps in obtaining pure metals without unwanted impurities, ensuring the quality of the final metal product.

Iron is extracted from the ore hematite, which is a form of iron oxide. Hematite is a primary source of iron and is widely used in the production of iron and steel due to its high iron content. Through the extraction process, iron can be obtained from hematite for various industrial applications.

Alloys play a crucial role in metallurgy by enhancing the strength and properties of metals. By combining two or more metals or a metal with a non-metal, alloys can exhibit improved mechanical, physical, and chemical properties compared to pure metals. This makes alloys essential in various industries for creating materials with specific characteristics suited for different applications.

Bronze is an alloy composed of copper and tin and is commonly used for making utensils, statues, and coins due to its durability, aesthetic appeal, and corrosion resistance. The use of bronze dates back to ancient civilizations, and it continues to be a popular choice for various applications requiring a combination of strength and workability.

Mercury is the primary metal used in dental alloy for filling teeth due to its unique properties that allow it to form a strong and durable filling material when combined with other metals. Dental amalgams, which consist of mercury along with silver, tin, and zinc, have been commonly used in dentistry for filling cavities and restoring teeth.

Constantan is an alloy composed of copper and nickel, known for its use in electrical apparatus due to its low thermal expansion and high electrical resistivity. Constantan is widely used in manufacturing resistors, thermocouples, and other electrical components where precise and stable electrical characteristics are required.

Brass, an alloy of copper and zinc, is widely used in making utensils, condenser tubes, musical instruments, and decorative items due to its attractive appearance, malleability, and corrosion resistance. Brass combines the strength of copper with the anti-corrosive properties of zinc, making it a versatile material for various applications.

Stainless steel is an alloy primarily designed to improve corrosion resistance in various applications. By combining iron with chromium, nickel, and other elements, stainless steel forms a protective layer that resists rust and corrosion, making it ideal for use in utensils, kitchen appliances, industrial equipment, and construction materials where durability and hygiene are essential.