Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can describe an ionic solid as a repeating three-dimensional array of cations and anions, and explain why it contains no molecules. (Guide: “What an ionic solid really is”; Practice Q1)
- I can explain why each ion is surrounded by ions of the opposite charge, in terms of attraction and repulsion. (Guide; Practice Q5)
- I can explain what a formula such as CaF₂ tells me about an ionic solid, and what it does not tell me. (Guide; Revision notes)
- I can explain why a cation is smaller than its atom and an anion is larger than its atom, and why isoelectronic ions differ in size. (Guide: “Ion sizes you can use”; Practice Q6)
Skills
- I can draw a particulate model of an ionic solid with alternating charges, sensible relative sizes, the formula ratio and labelled charges. (Guide: Figure 1; Practice Q5)
- I can find an error in someone else’s particulate model and correct it. (Guide: Worked example 1; Practice Q1)
- I can calculate the distance between ion centres from ionic radii and use |q₊q₋| / d to compare ionic solids. (Guide: Worked example 2; Practice Q6)
- I can rank ionic solids by strength of attraction, considering charge first and then ion size. (Practice Q2, Q3)
Reasoning
- I can explain why ionic solids are brittle, using what happens to the charges when a layer slides. (Guide: Figure 2; Practice Q4)
- I can explain why an ionic solid conducts electricity only when it is molten or dissolved. (Practice Q7)
- I can predict which of two ionic solids has the higher melting point and justify it with Coulomb’s law. (Guide: Worked example 2; Practice Q6)
All ticked? Move on to Topic 2.4, Structure of Metals and Alloys, or return to the course roadmap.