Tests for Anions
Specific chemical tests identify negative ions like carbonate, sulfate and halide in solutions.
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Specific chemical tests identify negative ions like carbonate, sulfate and halide in solutions.
- Carbonates fizz with acid
- Sulfates give a white precipitate with barium chloride
- Halides give coloured precipitates with silver nitrate
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Tests for Anions?
Within Chemistry, which covers atoms, bonding, reactions, the periodic table, organic chemistry and the chemistry of everyday life, this topic explains Tests for Anions. 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 Tests for Anions in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Tests for Anions helps you explain why substances behave as they do, from cleaning products and food to medicines.
Tests for Anions in detail
Anions are identified by simple tests. Carbonates fizz with dilute acid, releasing carbon dioxide that turns limewater cloudy. Sulfates give a white precipitate with barium chloride or barium nitrate after adding dilute hydrochloric acid. Halides give precipitates with silver nitrate after adding dilute nitric acid: chloride is white, bromide cream and iodide yellow.
Nitrates can be identified by reducing to ammonia with aluminium and sodium hydroxide. Acid is added first to remove carbonates that might give misleading results. These tests, combined with cation tests, identify unknown salts.
How the interactive helps you understand Tests for Anions
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 Tests for Anions.
Real-life uses and examples
- Use Tests for Anions to explain what happens in a lab experiment and why.
- Link Tests for Anions to everyday products such as cleaning agents, food and medicines.
- Read a chemical equation or diagram and work out what Tests for Anions shows.
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 Tests for Anions.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Tests for Anions
What is Tests for Anions?
Specific chemical tests identify negative ions like carbonate, sulfate and halide in solutions.
What are the most important points about Tests for Anions?
The main points are: Carbonates fizz with acid; Sulfates give a white precipitate with barium chloride; Halides give coloured precipitates with silver nitrate.
Why is Tests for Anions useful?
Understanding Tests for Anions helps you explain why substances behave as they do, from cleaning products and food to medicines.
How can I practise Tests for Anions?
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 Tests for Anions?
Related topics in Chemistry include Crystallisation, Chemistry of the Atmosphere Layers, Chemical Industry and Sustainability.