Flame Tests and Cation Tests
Flame tests and sodium hydroxide precipitates help identify metal ions in a compound.
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Flame tests and sodium hydroxide precipitates help identify metal ions in a compound.
- Sodium burns yellow
- Copper burns green
- Copper hydroxide is a blue precipitate
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Flame Tests and Cation Tests?
Within Chemistry, which covers atoms, bonding, reactions, the periodic table, organic chemistry and the chemistry of everyday life, this topic explains Flame Tests and Cation Tests. Chemistry links what you can see in the lab to the particles and bonds behind it, so each topic here shows that link in a model.
Check that you can explain Flame Tests and Cation Tests in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Flame Tests and Cation Tests helps you explain why substances behave as they do, from cleaning products and food to medicines.
Flame Tests and Cation Tests in detail
Metal ions give characteristic colours in a flame test: lithium crimson, sodium yellow, potassium lilac, calcium orange-red and copper blue-green. A clean wire loop is dipped in the sample and held in a blue Bunsen flame.
Sodium hydroxide solution identifies many metal ions by the colour of the hydroxide precipitate: copper(II) gives blue, iron(II) green, iron(III) brown, and aluminium, calcium and magnesium give white. Aluminium dissolves in excess alkali, but magnesium and calcium do not. Ammonium ions release ammonia gas on warming with sodium hydroxide.
How the interactive helps you understand Flame Tests and Cation Tests
Click a step, or use the Previous and Next buttons, to move through the sequence one stage at a time. Auto-play moves on for you.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Flame Tests and Cation Tests.
Real-life uses and examples
- Read a chemical equation or diagram and work out what Flame Tests and Cation Tests shows.
- Explain Flame Tests and Cation Tests in an exam by linking the particles involved to what you observe.
- Use Flame Tests and Cation Tests to explain what happens in a lab experiment and why.
Common mistakes to avoid
- Describing what happens without explaining the particles or bonds involved.
- Mixing up the names of substances or ions when you describe Flame Tests and Cation Tests.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Flame Tests and Cation Tests
What is Flame Tests and Cation Tests?
Flame tests and sodium hydroxide precipitates help identify metal ions in a compound.
What are the most important points about Flame Tests and Cation Tests?
The main points are: Sodium burns yellow; Copper burns green; Copper hydroxide is a blue precipitate.
Why is Flame Tests and Cation Tests useful?
Understanding Flame Tests and Cation Tests helps you explain why substances behave as they do, from cleaning products and food to medicines.
How can I practise Flame Tests and Cation Tests?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Flame Tests and Cation Tests?
Related topics in Chemistry include Solubility and Saturated Solutions, Thermal Decomposition, Alloys.