Tests for Gases

What is Tests for Gases?

Within Chemistry, which covers atoms, bonding, reactions, the periodic table, organic chemistry and the chemistry of everyday life, this topic explains Tests for Gases. 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 Gases 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 Gases helps you explain why substances behave as they do, from cleaning products and food to medicines.

Tests for Gases in detail

Simple tests identify common gases. Hydrogen makes a lit splint give a squeaky pop. Oxygen relights a glowing splint. Carbon dioxide turns limewater milky (cloudy) because calcium carbonate forms. Chlorine bleaches damp blue litmus paper, turning it white, and it has a pungent, poisonous smell.

Ammonia turns damp red litmus paper blue and has a sharp smell. Always perform gas tests with care and in a ventilated area, and know the reason behind each result. These tests allow you to identify the products of a reaction.

How the interactive helps you understand Tests for Gases

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 Gases.

Real-life uses and examples

• Explain Tests for Gases in an exam by linking the particles involved to what you observe.
• Use Tests for Gases to explain what happens in a lab experiment and why.
• Link Tests for Gases to everyday products such as cleaning agents, food and medicines.

Common mistakes to avoid

• Mixing up the names of substances or ions when you describe Tests for Gases.
• Describing what happens without explaining the particles or bonds involved.
• Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.