The process of extracting metals from their ores by heating beyond the melting point.
Explanation
Smelting is a pyrometallurgical process used to extract base metals from their ores. It involves heating the ore to a temperature beyond its melting point, often in the presence of a reducing agent (such as coke) and a flux (such as limestone), to separate the pure metal from impurities.
Option Analysis:
- The process of shaping steel into wires. is incorrect: The process of shaping steel or other metals into wires is known as drawing. It involves pulling metal through a die to reduce its cross-section.
- The process of extracting metals from their ores by heating beyond the melting point. is correct: Smelting specifically refers to the extraction of metal from its ore by heating it beyond the melting point. This process causes the metal to melt and separate from the gangue (impurities), which is removed as slag. It is the primary process used in the iron and steel industry (e.g., in a blast furnace).
- The process of mixing wood pulp with chemicals to make paper. is incorrect: The process of mixing wood pulp with chemicals to manufacture paper is part of pulping or papermaking, unrelated to metallurgy.
- The process of weaving cotton into fabric. is incorrect: The process of weaving cotton into fabric is a textile manufacturing process, distinct from metallurgical extraction.
Key Takeaway:
Smelting is the thermal processing of ore to extract metal (reduction), distinct from physical shaping processes like casting, forging, or drawing.