Stages in Metal Processing and Forms of Metals

Subject: Basic Technology

Class: JSS 3
Term: First Term
Week: 2
Age: 13 years

Topic: Processing of Metals
Sub-topic: Stages in Metal Processing and Forms of Metals

Duration: 40 minutes

Behavioural Objectives:
By the end of the lesson, students should be able to:

1. Define metal processing and explain how metals are obtained from ores.
2. Describe the stages involved in metal processing.
3. List different methods of forming metals.
4. Identify various forms of metals and their uses.

Keywords: Metal processing, Ore, Smelting, Casting, Forming, Iron ore

Set Induction:
Display a sample of a metal rod and ask students how they think metals are produced from the ground. Lead the discussion towards the metal extraction process.

Entry Behaviour:
Students are familiar with the use of metals in their daily lives, such as for construction, tools, and appliances.

Learning Resources and Materials:

• Samples of metal ores and refined metals
• Pictures of metal processing stages
• Charts showing metal forms and shapes

Building Background / Connection to Prior Knowledge:
Students have previously learned about the properties of metals in Basic Technology.

Embedded Core Skills:

• Critical thinking
• Problem-solving
• Observation

Learning Materials:

• Lagos State Scheme of Work
• Basic Technology textbooks
• Metal samples

Reference Books:

• Lagos State Basic Technology Scheme of Work

Instructional Materials:

• Metal samples
• Charts on metal processing and forming methods

Content

Definition of Metal Processing
Metal processing involves extracting metals from their ores and refining them for industrial use. Metals are found in the form of ores beneath the ground and are extracted using various methods.

Stages in Metal Processing

1. Extraction:
   Metals are extracted from their ores, which are rocks that contain metal compounds.
2. Smelting:
   After extraction, the metal ore is heated to a molten state in a furnace. This process separates the metal from impurities such as sand, phosphorus, and silicon. The impurities form a substance called slag, which is removed.
   • Materials needed for smelting:
     • Iron ore
     • Limestone
     • Coke (a type of coal used as fuel)
3. Casting:
   The molten metal is poured into a mold and allowed to cool and solidify. This produces cast iron or other shaped metal products.
4. Forming:
   Forming is the process of shaping or bending metals into different shapes using force. There are different methods of forming metals, including:
   • Spinning
   • Extrusion
   • Drawing

Types of Iron Ore

1. Limonite
2. Magnetite (Iron II oxide)
3. Hematite (Iron III oxide)

Forms of Metals

1. Round bars
2. Sheets
3. Tubes
4. Channels
5. Rolls
6. Wires
7. Rectangular/Square bars
8. Strips

Evaluation

1. The process of removing impurities from metal ore is called __________.
   a) Smelting
   b) Extraction
   c) Melting
   d) Refining
2. Iron is produced from __________.
   a) Aluminum ore
   b) Iron ore
   c) Copper ore
   d) Gold ore
3. The impurities removed during smelting form a substance called __________.
   a) Slag
   b) Sand
   c) Iron
   d) Ore
4. The process of pouring molten metal into a mold is called __________.
   a) Casting
   b) Forming
   c) Extrusion
   d) Spinning
5. __________ is used to separate metal from its impurities in a furnace.
   a) Limestone
   b) Water
   c) Fire
   d) Iron oxide
6. Forming metals into shape using force is called __________.
   a) Smelting
   b) Casting
   c) Forming
   d) Heating
7. Metals in the form of sheets are referred to as __________.
   a) Tubes
   b) Rolls
   c) Channels
   d) Sheets
8. __________ is an example of iron ore.
   a) Bauxite
   b) Hematite
   c) Quartz
   d) Limestone
9. The impurities removed from molten iron during smelting are called __________.
   a) Gold
   b) Slag
   c) Coke
   d) Ore
10. Metals used for making wires are in the form of __________.
    a) Sheets
    b) Rolls
    c) Wires
    d) Tubes

Class Activity Discussion:

1. What is metal processing?
   Metal processing is the process of extracting metals from ores and refining them for industrial use.
2. How are metals extracted from the ground?
   Metals are extracted from ores, which are rocks that contain metal compounds.
3. What is smelting?
   Smelting is the process of heating metal ore to a molten state to remove impurities.
4. What is slag?
   Slag is the impurities removed from metal during smelting, such as sand and phosphorus.
5. What is the purpose of casting?
   Casting is done to shape the molten metal by pouring it into a mold to cool and solidify.
6. What is forming?
   Forming is the process of shaping or bending metals into desired shapes using force.
7. What materials are needed for smelting?
   Materials needed for smelting include iron ore, limestone, and coke.
8. What is an iron ore?
   Iron ore is a rock that contains iron and is used to produce iron metal.
9. What is the role of limestone in smelting?
   Limestone helps to remove impurities during the smelting process.
10. What is extrusion?
    Extrusion is a forming method where metal is pushed through a mold to create specific shapes.
11. What is drawing?
    Drawing is a method used to shape metal by pulling it through a die.
12. What happens to the molten metal during casting?
    It is poured into a mold to cool and solidify into a specific shape.
13. Why are metals formed into different shapes?
    Metals are formed into different shapes to suit their various industrial uses.
14. What are the forms of metal?
    Metals can come in forms such as round bars, sheets, tubes, and wires.
15. What is magnetite?
    Magnetite is a type of iron ore used to produce iron.

Presentation

Step 1: The teacher revises the previous lesson on the properties of metals.

Step 2: The teacher explains the stages involved in metal processing, from extraction to forming, with examples.

Step 3: Students share their understanding of metal production, and the teacher corrects their contributions.

Activities

Teacher’s Activities:

• Display metal samples and charts showing metal processing stages.
• Explain the process of smelting and forming.
• Discuss the different forms of metals and their uses.

Learner’s Activities:

• Observe the metal samples and forms.
• Participate in the discussion on metal processing and forming.
• Answer questions on metal extraction and smelting.

Assessment

Evaluation Questions:

1. What is metal processing?
2. List two stages in metal processing.
3. What is the role of smelting in metal production?
4. Why is casting important in metal production?
5. Name two types of iron ore.
6. What are the materials used for smelting?
7. Describe the process of forming metal.
8. Name two forms of metals.
9. What is slag?
10. What is the difference between casting and forming?

Conclusion:

The teacher moves around the class, checking students’ notes and providing feedback. The lesson ends with a recap of the metal processing stages and forming methods.