This topic summary covers Topic Summary: Flame Tests within Flame Tests for GCSE Chemistry. Revise Flame Tests in Chemical Analysis for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. 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
15 flashcards
Topic Summary: Flame Tests
Flame Colours
- Li⁺ = Crimson red
- Na⁺ = Orange-yellow
- K⁺ = Lilac/purple
- Ca²⁺ = Orange-red (brick red)
- Cu²⁺ = Blue-green
Method Steps
- Dip wire in dilute HCl
- Heat until no colour
- Dip in HCl then sample
- Hold in blue flame
- Observe colour immediately
Science Behind It
- Heat excites electrons to higher levels
- Electrons fall back to ground state
- Energy released as coloured light
- Each element has unique energy gaps → unique colour
Limitations
- Not all metals give colours
- Similar colours can be confused
- Sodium contamination common
- Blue glass needed for potassium