Bonding in Metals

Learning Objectives (WALT)

• WALT describe the structure of metals as a giant lattice of positive ions in a sea of delocalised electrons.
• WALT explain metallic bonding and how it gives metals their characteristic properties.
• WALT represent metallic bonding diagrammatically and interpret models of metallic bonding.
• WALT evaluate the relationship between metallic structure and properties such as conductivity, malleability, and melting point.

Success Criteria

• I can identify the giant metallic lattice structure and explain what the “sea of electrons” means.
• I can describe metallic bonds and represent them in diagrams using correct scientific vocabulary.
• I can relate the structure of metals to their physical properties like electrical conductivity and malleability.
• I can answer exam-style questions accurately, explaining metallic bonding and its effects.

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National Curriculum Links

• KS3 Science – Chemistry – Structure and Bonding (C3.9 Metallic Bonding)
  Pupils should be taught that metals consist of atoms arranged in a giant lattice and that metallic bonding involves delocalised electrons. They should understand how this explains properties such as conductivity and malleability.
• Working scientifically: Drawing and interpreting diagrams and models of atomic structure.
• Programme of Study - Science:
  Pupils should be able to explain properties of materials in terms of particle arrangements, including metals.

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Lesson Structure (60 Minutes)

Starter (10 minutes)

• Activity: Name and complete starter task on fullerenes to connect with previous learning, activating prior knowledge about bonding and structure in materials.
• Purpose: Recap carbon allotropes to scaffold understanding of bonding variety leading to metallic bonding.

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Introduction to Metallic Bonding (10 minutes)

• Use slides from Bonding in metals-TLA.pptx to explain:
  • Metal atoms arranged in layers in a giant metallic lattice.
  • Valence electrons are delocalised, free to move, forming a "sea of electrons."
  • Electrostatic attraction between positive metal ions and delocalised electrons is metallic bonding.
• Show diagrams illustrating metallic bonding.
• Use clear scientific terminology: lattice, ions, delocalised electrons, electrostatic forces.

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Main Activity 1 — Diagrammatic Modelling (15 minutes)

• Paired Task: On mini whiteboards, students draw diagrams of metallic bonding with labelled parts: positive ions, delocalised electrons, layers.
• Differentiation: Provide a dyslexia-friendly sheet with key terms and images to support writing and spelling.
• Teacher Facilitation: Circulate while students draw, prompting deeper thinking with questions:
  • “What do the ions look like?”
  • “Why do these electrons move freely?”
  • “How would this structure conduct electricity?”

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Main Activity 2 — Practical/Demo (15 minutes)

• Growing Silver Crystals Demonstration (from TLA):
  • Teacher sets up copper wire in silver nitrate solution beforehand.
  • Students observe and note crystal formation over time, relating it to reactivity and bonding concepts.
• Class Discussion:
  • How does the metallic bonding affect the properties of silver and copper?
  • How might this relate to reactivity and displacement?
• Students write a brief explanation linking metallic structure to practical observations.

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Plenary – Exam Questions (10 minutes)

• Full class attempts exam question from reference material:
  • Describe key features shown in two diagrams of a metal’s structure.
  • Explain how metallic bonding works.
  • Extend explanation to properties: conductivity, malleability, melting point.
• Peer assessment: Swap answers and mark using success criteria.
• Teacher feedback highlights model answers and common misconceptions.

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Differentiation

• Support: Use graphic organisers with labelled diagrams and key terms for lower ability or EAL pupils.
• Dyslexia-Friendly: Print word banks with large font; use bullet points, avoid dense text. Use multi-sensory approaches (visuals + spoken explanations).
• Challenge: Extension task—research and explain how metallic bonding differs in alloys or what happens when metals are bent (introduce sliding of layers and ion movement).

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Assessment

• Formative assessment through paired whiteboard drawing and teacher questioning.
• Summative assessment via exam-style Q&A, peer and teacher mark.
• Observation of participation and understanding during practical demo discussions.

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Resources

• Whiteboards and pens
• PowerPoint slides from Bonding in metals-TLA.pptx
• Copper wire, silver nitrate solution, conical flask, splints (for demonstration)
• Printed dyslexia-friendly word banks & diagrams

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Extension/Homework

• Research everyday uses of metals (e.g., copper wiring, aluminium cans) and explain how metallic bonding contributes to their suitability.
• Create an illustrated poster describing metallic bonding and its effects on physical properties.

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This lesson engages Year 9 learners with comprehensive, scaffolded activities fully aligned to the National Curriculum structure and bonding unit (C3.9). It strengthens conceptual understanding using multi-modal teaching, practical demonstrations, and assessment for learning to deepen their grasp of metallic bonding and related properties.