Starter quiz
- Which type of bonding involves the sharing of pairs of electrons between atoms?
- Ionic bonding
- Covalent bonding ✓
- Metallic bonding
-
- Which type of bonding occurs between metal atoms, allowing them to conduct electricity?
- Ionic bonding
- Covalent bonding
- Metallic bonding ✓
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- In ______ bonding, one atom donates electrons to another atom, creating positive and negative ions that attract each other.
- 'ionic' ✓
- ______ diagrams use crosses and dots to represent the electrons from different atoms. It shows how these electrons are shared to form covalent bonds.
- 'dot-and-cross' ✓
- Which of the following substances is most likely to have covalent bonding?
- Sodium chloride (NaCl)
- Magnesium oxide (MgO)
- Methane (CH₄) ✓
- Aluminum (Al)
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- When a metal atom loses electrons, it becomes a ______ charged ion.
- 'positively' ✓
Exit quiz
- Which model is used to show how chemical bonds are formed between atoms?
- Space-filling model
- Ball-and-stick model
- Dot-and-cross diagram ✓
- Displayed formula
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- Which model is best for showing the relative sizes of atoms?
- Space-filling model ✓
- Ball-and-stick model
- Dot-and-cross diagram
- Displayed formula
-
- Which model can only be used to show covalent bonds (not ionic bonds)?
- Space-filling model
- Ball-and-stick model
- Dot-and-cross diagram
- Displayed formula ✓
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- Which of the following is a key advantage of the displayed formula?
- It shows the three-dimensional shape of molecules.
- It accurately represents the sizes of atoms.
- It clearly shows all atoms and bonds in a molecule. ✓
- It shows how electrons are shared between atoms.
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- Which model are these statements about? Advantage: It clearly shows which electrons come from which atom. Limitation: It does not show the 3D structure of the chemical.
- Ball-and-stick model
- Dot-and-cross diagram ✓
- Space-filling model
- Displayed formula
-
- The space-filling model is useful for visualising molecular size and shape, while the ______ model shows the 3D arrangement of atoms and bonds, which helps visualise molecular geometry.
- 'ball-and-stick' ✓
Worksheet
Presentation
Video
Lesson Details
Key learning points
- Scientists use models to represent parts of the natural world that are too difficult to observe or explain directly.
- There are multiple ways (models) of drawing/showing bonding.
- There are multiple advantages and limitations of particular representations and models.
Common misconception
Understanding that the models used to represent chemical story do not tell the complete story. Different models can be used to explain different aspects of bonding, but they all have limitations.
Avoid telling your class that the model is wrong; rather stress its limitations. Stress the idea that as we learn more about bonding, we will be able to use more sophisticated models to show and explain more key ideas.
Keywords
Model - used by scientists to represent parts of the natural world that are too difficult to observe or explain directly
Ball-and-stick model - used to represent the atoms and bonds in a chemical compound
Dot-and-cross diagram - used to show how chemical bonds are formed between atoms
Space-filling model - a 3D molecular model where the atoms are represented by spheres
Displayed formula - a 2D model of a covalent substance, showing all its atoms and bonds