General Principles and Processes of Isolation of Elements – Class 12 Chemistry Notes | Complete NCERT Summary
🧪 Chapter 6: General Principles and Processes of Isolation of Elements --- 🔹 Introduction This chapter deals with metallurgy – the process of extracting pure metal from its ores. Metallurgy steps: Concentration → Extraction → Refining --- 🔹 Occurrence of Metals Native State: e.g., gold, platinum Combined State: Most metals found as oxides, sulphides, carbonates, halides etc. --- 🔹 Steps in Metallurgy 1️⃣ Concentration of Ore Removes impurities (gangue). Methods: Gravity separation (hydraulic washing) Magnetic separation Froth flotation (for sulphide ores) Leaching (for Al, Ag) 📌 Diagram: Froth flotation process setup --- 2️⃣ Extraction of Crude Metal By reduction of oxides: Using carbon (smelting) Using more reactive metals (Al in thermite process) By electrolytic reduction 📌 Diagram: Blast furnace for iron extraction --- 3️⃣ Refining of Metal Distillation Liquation Electrolytic refining Zone refining (for semiconductors like Si, Ge) 📌 Diagram: Electrolytic refining of copp...