Atomic StructureTopic Summary
Knowledge Organiser: Group 1 Alkali Metals
Part of Group 1: Alkali Metals · GCSE GCSE Chemistry revision
This topic summary covers Knowledge Organiser: Group 1 Alkali Metals within Group 1: Alkali Metals for GCSE Chemistry. Revise Group 1: Alkali Metals in Atomic Structure for GCSE Chemistry with 20 exam-style questions and 20 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 13 of 13
Practice
20 questions
Recall
20 flashcards
Knowledge Organiser: Group 1 Alkali Metals
Key Terms
- Alkali metals: Group 1, 1 outer electron
- Reactivity trend: Increases down Group 1
- Shielding: Inner electrons reduce nuclear pull
- Metal hydroxide: Product of water reaction
Must-Know Facts
- Soft, low density, low melting point
- Stored under oil (prevent air/water reaction)
- React with water → hydroxide + hydrogen
- 2Na + 2H₂O → 2NaOH + H₂
- React with chlorine → metal chloride (e.g., 2Na + Cl₂ → 2NaCl)
- Li: gentle fizz; Na: vigorous; K: lilac flame
- Reactivity increases ↓ (outer electron further, weaker attraction)
Key Equations
- 2Li + 2H₂O → 2LiOH + H₂
- 2Na + 2H₂O → 2NaOH + H₂
- 2K + 2H₂O → 2KOH + H₂
- 2Na + Cl₂ → 2NaCl
Common Mistakes
- Forgetting hydrogen gas is produced: Alkali metals + water → metal hydroxide AND hydrogen — both products are needed for full marks
- Saying reactivity decreases down Group 1: It increases — the outer electron is further from the nucleus and more easily lost
- Missing the 2 coefficient: The equation is 2Na + 2H₂O → 2NaOH + H₂ — students often write Na + H₂O → NaOH + H
- Saying melting points increase down Group 1: They decrease — larger atoms have weaker metallic bonding