Bonding & StructureDeep Dive

Understanding Ionic Bonding Step by Step

Part of Ionic Bonding · GCSE GCSE Chemistry revision

This deep dive covers Understanding Ionic Bonding Step by Step within Ionic Bonding for GCSE Chemistry. Revise Ionic Bonding in Bonding & Structure for GCSE Chemistry with 35 exam-style questions and 20 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 3 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 3 of 16

Practice

35 questions

Recall

20 flashcards

🔬 Understanding Ionic Bonding Step by Step

Let's walk through sodium chloride (NaCl) — table salt:

Step 1: Sodium atom (Na)
• Electron configuration: 2,8,1
• Has 1 electron in outer shell
• Loses this electron to achieve a stable 2,8 configuration (like neon)
• 11 protons, 11 electrons → neutral
Step 2: Chlorine atom (Cl)
• Electron configuration: 2,8,7
• Has 7 electrons in outer shell — one electron short of a stable configuration
• Gains 1 electron to achieve a stable 2,8,8 configuration (like argon)
• 17 protons, 17 electrons → neutral
Step 3: Electron Transfer
• Sodium's outer electron jumps to chlorine
• This is a chemical reaction — atoms change!
• Neither atom is neutral anymore
Step 4: Ions Form
• Sodium: 11 protons, 10 electrons → Na⁺ (positive ion = CATION)
• Chlorine: 17 protons, 18 electrons → Cl⁻ (negative ion = ANION)
• Both now have full outer shells!
Step 5: Ionic Bond Forms
• Na⁺ and Cl⁻ are oppositely charged
• Opposite charges attract (electrostatic attraction)
• This attraction IS the ionic bond
• Very strong — takes lots of energy to break!

Why do Group 1 metals form +1 ions? They have 1 outer electron to lose.
Why do Group 2 metals form +2 ions? They have 2 outer electrons to lose.
Why do Group 7 elements form -1 ions? They are 1 electron short of a stable full outer shell.
Why do Group 6 elements form -2 ions? They are 2 electrons short of a stable full outer shell.

The Charge Rule: The charge on an ion = number of electrons lost or gained. Metals lose electrons (positive charge), non-metals gain electrons (negative charge). The number equals how far they are from a full shell!

Keep building this topic

Read this section alongside the surrounding pages in Ionic Bonding. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Ionic Bonding

Which combination of elements forms an ionic compound?

  • A. Sodium and chlorine
  • B. Carbon and hydrogen
  • C. Nitrogen and oxygen
  • D. Carbon and oxygen
1 markfoundation

Describe the structure of an ionic compound and explain why ionic compounds have high melting points. [3 marks]

3 marksstandard

Quick Recall Flashcards

What is a cation?
A positive ion (formed when metals lose electrons)
What is an anion?
A negative ion (formed when non-metals gain electrons)

35 questions on Ionic Bonding — practise free

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