4.1.2 Extraction of metals and reduction

• What are ores in the context of metal extraction?

  Rocks containing metal compounds
• Smelting is used for highly reactive metals like aluminum

  False
• In metal extraction, reduction involves the gain of electrons
• Reduction is a process where the oxidation state increases

  False
• Steps of the reduction process in smelting

  1️⃣ Metal ore is heated with carbon

  2️⃣ Carbon donates electrons to metal ions

  3️⃣ Metal ions are reduced to metallic state
• What is the common outcome of all reduction reactions in metal extraction?

  Pure metallic element
• Steps of the displacement reaction method

  1️⃣ Metal ore is dissolved in acid

  2️⃣ A more reactive metal is added

  3️⃣ The more reactive metal donates electrons

  4️⃣ The less reactive metal precipitates out
• Electrolysis involves passing an electric current through a dissolved or melted metal compound.


  True
• Match the extraction method with its reducing agent:

  Smelting ↔️ Carbon (Coke)

  Electrolysis ↔️ Electric current
• Steps in the displacement reaction method

  1️⃣ Dissolve metal ore in acid

  2️⃣ Add more reactive metal

  3️⃣ Reactive metal donates electrons

  4️⃣ Less reactive metal precipitates out
• In the displacement reaction method, a more reactive metal like iron or zinc is added to the solution.
• What type of metals is electrolysis commonly used to extract?

  Highly reactive metals
• Steps in the electrolysis process

  1️⃣ Dissolve or melt metal compound

  2️⃣ Pass electric current through solution

  3️⃣ Reduction at cathode

  4️⃣ Oxidation at anode
• Match the extraction method with its metal compound type:

  Smelting ↔️ Oxides or sulfides

  Electrolysis ↔️ Halides or oxides
• In electrolysis, an electric current provides the electrons to reduce metal ions at the cathode.
• The displacement reaction method uses a more reactive metal to displace a less reactive metal from its compound.


  True
• The displacement reaction method is more energy-intensive than smelting.

  False
• Electrolysis uses an electric current to extract metals from ores.
• Steps of the electrolysis process

  1️⃣ Dissolve or melt metal compound

  2️⃣ Pass electric current

  3️⃣ Reduction at cathode

  4️⃣ Oxidation at anode
• Reactive metals react vigorously with water, while unreactive metals do not.


  True
• What are the three main metal extraction methods mentioned in the text?

  Smelting, Electrolysis, Displacement
• The methods used for metal extraction depend on the reactivity of the metal
• Match the extraction method with the type of metal it's used for:

  Smelting ↔️ Moderately reactive metals

  Electrolysis ↔️ Highly reactive metals
• What is the reducing agent used in smelting for iron extraction?

  Carbon (Coke)
• What happens to the oxidation state during reduction?

  It decreases
• In electrolysis, metal ions gain electrons at the cathode
• The displacement reaction method is used for highly reactive metals

  False
• The displacement reaction method is typically used for extracting metals less reactive than iron
• In smelting, metal ore is heated with coke in a furnace to reduce the metal oxide.
• What happens to metal ions during reduction in metal extraction?

  They gain electrons
• Smelting is used to extract metals like iron and copper using carbon as a reducing agent.
• The displacement reaction method is more energy-intensive than smelting or electrolysis.

  False
• In electrolysis, metal ions are reduced at the cathode.

  True
• During electrolysis, the other element at the anode is oxidized and released as a gas.
• Metal extraction involves obtaining metals from their ores.


  True
• What is the reducing agent used in smelting?

  Carbon (Coke)
• Steps in the displacement reaction method

  1️⃣ Dissolve metal ore in acid

  2️⃣ Add more reactive metal

  3️⃣ Reactive metal donates electrons

  4️⃣ Less reactive metal precipitates out
• The displacement reaction method uses a more reactive metal to displace a less reactive metal from its compound
• Steps of the displacement reaction method

  1️⃣ Metal ore is dissolved in an acid

  2️⃣ More reactive metal is added

  3️⃣ Reactive metal donates electrons

  4️⃣ Less reactive metal precipitates
• Oxidation occurs at the cathode in electrolysis.

  False