2.4.1—Bonding continuum

Syllabus
First assessment 2025
Objective
2.4.1
Level
HL

The Bonding Continuum

Ionic, covalent, and metallic bonding are models whose contributions can vary across materials. The bonding continuum represents mixed character rather than completely separate categories.

Use the relative contributions of the three bonding types to explain a material's position and its likely properties.

Treat the three bonding models as coordinates rather than sealed boxes. A material may combine electron sharing with partial charge separation, so its properties can fall between idealized categories. Explain which model contribution accounts for each observed property instead of assigning one label and stopping.

Applying the Bonding Continuum

Assessment in practice

Representative question

Question 1

[Maximum number: 4]

State the types of bonding in magnesium, oxygen and magnesium oxide, and how the valence electrons produce these types of bonding.

SubstanceBond typeHow the valence electrons produce these bonds
Magnesium..........
____\_\_\_\_____\_\_\_\_
Oxygen..........____\_\_\_\_
Magnesium oxide..........____\_\_\_\_

Models to Materials Summary

Retrieve the pathway: locate bonding contributions, connect them to material properties, distinguish alloy lattice disruption, and construct addition or condensation polymer repeating units from monomer evidence.

Check that the bonding description matches the material, the property explanation names the structural cause, and every polymer substituent, continuation bond, and released small molecule is represented.