3.2 AS Level

Ionic bonding

Cambridge A-Level Chemistry (9701)  · Unit 3: Chemical bonding  · 6 flashcards

Ionic bonding is topic 3.2 in the Cambridge A-Level Chemistry (9701) syllabus , positioned in Unit 3 — Chemical bonding , alongside Electronegativity and bonding, Metallic bonding and Shapes of molecules.  In one line: Ionic bonding is the electrostatic attraction between oppositely charged ions. These ions are formed through the transfer of electrons, creating positively charged cations and negatively charged anions.

Marked as AS Level: examined at AS Level in Paper 1 (Multiple Choice), Paper 2 (AS Structured Questions) and Paper 3 (Advanced Practical Skills). The same content may also be assumed in Paper 4 (A Level Structured Questions).

The deck below contains 6 flashcards — 1 definition and 5 key concepts — covering the precise wording mark schemes reward.  Use the definition card to lock down command-word answers (define, state), then move on to the concept and calculation cards to handle explain, describe, calculate and compare questions.

Key definition

Ionic bonding

Ionic bonding is the electrostatic attraction between oppositely charged ions. These ions are formed through the transfer of electrons, creating positively charged cations and negatively charged anions.

What the Cambridge 9701 syllabus says

Official 2025-2027 spec · AS Level

These are the exact learning outcomes Cambridge sets for this topic. The candidate is expected to be able to do each of these on the relevant paper.

  1. define ionic bonding as the electrostatic attraction between oppositely charged ions (positively charged cations and negatively charged anions)
  2. describe ionic bonding including the examples of sodium chloride, magnesium oxide and calcium fluoride
  3. www.cambridgeinternational.org/alevel

Cambridge syllabus keywords to use in your answers

These are the official Cambridge 9701 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.

ionic bonding electrostatic attraction cations anions sodium chloride magnesium oxide calcium fluoride

Tips to avoid common mistakes in Ionic bonding

Definition Flip

Define ionic bonding.

Answer Flip

Ionic bonding is the electrostatic attraction between oppositely charged ions. These ions are formed through the transfer of electrons, creating positively charged cations and negatively charged anions.

Key Concept Flip

Describe the formation of sodium chloride (NaCl) through ionic bonding.

Answer Flip

Sodium (Na) loses one electron to become a Na⁺ cation. Chlorine (Cl) gains one electron to become a Cl⁻ anion. The electrostatic attraction between Na⁺ and Cl⁻ forms the ionic bond in NaCl.

Key Concept Flip

Describe the formation of magnesium oxide (MgO) through ionic bonding.

Answer Flip

Magnesium (Mg) loses two electrons to become a Mg²⁺ cation. Oxygen (O) gains two electrons to become an O²⁻ anion. The electrostatic attraction between Mg²⁺ and O²⁻ forms the ionic bond in MgO.

Key Concept Flip

Describe the formation of calcium fluoride (CaF₂) through ionic bonding.

Answer Flip

Calcium (Ca) loses two electrons to become a Ca²⁺ cation. Two fluorine (F) atoms each gain one electron to become two F⁻ anions. The electrostatic attraction between Ca²⁺ and two F⁻ ions forms the ionic bond in CaF₂.

Key Concept Flip

What is the relationship between charge magnitude and the strength of an ionic bond?

Answer Flip

The greater the magnitude of the charge on the ions, the stronger the electrostatic attraction and thus the stronger the ionic bond.

Example: MgO (Mg²⁺ and O²⁻) has a stronger ionic bond than NaCl (Na⁺ and Cl⁻).
Key Concept Flip

What type of elements typically form ionic bonds?

Answer Flip

Ionic bonds typically form between metals (which readily lose electrons to form cations) and non-metals (which readily gain electrons to form anions).

More Chemistry flashcards

Browse every 9701 flashcard topic by syllabus area.

All Chemistry Flashcards
3.1 Electronegativity and bonding 3.3 Metallic bonding

More topics in Unit 3 — Chemical bonding

Ionic bonding sits alongside these A-Level Chemistry decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.

Key terms covered in this Ionic bonding deck

Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.

Ionic bonding

How to study this Ionic bonding deck

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