4.1.2 Extraction of metals and reduction

• Steps involved in metal extraction

  1️⃣ Ore processing

  2️⃣ Metal reduction
• Understanding reduction is essential for obtaining pure metals from their ores.


  True
• Order the following metal extraction methods based on their typical process flow:

  1️⃣ Smelting

  2️⃣ Electrolysis

  3️⃣ Leaching
• Why is carbon used as a reducing agent in metallurgy?

  Effectiveness and availability
• What is the role of reduction in metallurgy?

  Converts metal ions
• What is the second step in metal extraction after ore processing?

  Metal reduction
• What happens to the oxidation number during reduction in metallurgy?

  Decreases
• Arrange the following features to distinguish between oxidation and reduction:

  1️⃣ Electron Transfer: Loses electrons in oxidation ||| Electron Transfer: Gains electrons in reduction

  2️⃣ Oxidation Number: Increases in oxidation ||| Oxidation Number: Decreases in reduction

  3️⃣ Oxygen Presence: Adds oxygen in oxidation ||| Oxygen Presence: Removes oxygen in reduction
• Electrolysis uses an electric current to reduce metal compounds.
• Metal extraction is the process of taking metals from their naturally occurring compounds
• In metallurgy, reduction involves the gaining of electrons
• Reduction involves the removal of oxygen from metal compounds.


  True
• Different metal extraction methods have varying environmental impacts.


  True
• Using carbon as a reducing agent in metallurgy is a cost-effective process.


  True
• Ore processing prepares the ore by concentrating metal compounds
• Match the process step with its description:

  Ore processing ↔️ Prepares the ore by concentrating metal compounds

  Metal reduction ↔️ Converts metal compounds into elemental metal
• In reduction, oxygen is removed from metal compounds.

  True
• What is the primary purpose of smelting in metal extraction?

  Separates metal from compounds
• The choice of metal extraction method depends on the ore composition, cost-effectiveness, and environmental considerations.

  True
• Using carbon as a reducing agent releases greenhouse gases.

  True
• Arrange the steps in smelting:

  1️⃣ Ore Preparation: Crushing and concentrating the ore

  2️⃣ Reduction: Heating with a reducing agent

  3️⃣ Separation: Isolating molten metal from impurities
• What is the process called that uses an electric current to reduce aluminum ions in molten aluminum oxide?

  Electrolysis
• Steps in the electrolysis of aluminum

  1️⃣ Dissolve aluminum oxide in cryolite

  2️⃣ Pass electric current

  3️⃣ Collect aluminum at cathode
• Reduction in metallurgy involves converting metal ions into metallic form by gaining electrons
• Carbon reacts with metal oxides at high temperatures to produce pure metal and carbon dioxide or carbon monoxide
• In the smelting of iron, carbon is added as a reducing agent.
• Steps involved in the smelting of iron ore

  1️⃣ Prepare the iron ore by crushing and concentrating it

  2️⃣ Add carbon as a reducing agent

  3️⃣ Heat the mixture in a furnace

  4️⃣ Separate the molten iron from the slag
• Steps involved in the electrolysis of aluminum

  1️⃣ Dissolve the aluminum oxide in molten cryolite

  2️⃣ Pass an electric current through the molten mixture

  3️⃣ Collect the pure aluminum metal at the cathode
• Match the metal extraction method with its key characteristics:

  Smelting ↔️ Uses carbon as a reducing agent

  Electrolysis ↔️ Uses electric current
• Smelting produces slag as a waste product, which must be disposed of carefully
• The primary purpose of metal extraction is to obtain metals in a usable form for various applications.


  True
• In metallurgy, reduction converts metal ions into metallic form by gaining electrons
• Smelting involves heating the metal ore with a reducing agent
• In the extraction of iron from iron oxide, carbon reacts to form iron and carbon monoxide
• In reduction, the oxidation number of metal ions increases.

  False
• The primary purpose of metal extraction is to obtain metals in a usable form.


  True
• During reduction, metal ions gain electrons
• Match the feature with its correct process:

  Electron Transfer ↔️ Loses electrons in oxidation, gains electrons in reduction

  Oxygen Presence ↔️ Adds oxygen in oxidation, removes oxygen in reduction

  Oxidation Number ↔️ Increases in oxidation, decreases in reduction
• Arrange the steps involved in leaching:

  1️⃣ Dissolve metal compounds using chemical solvents

  2️⃣ Recover metal from the solution
• Carbon reacts with metal oxides to produce pure metal and carbon dioxide or carbon monoxide.