Context
The air that we breathe is a mixture of gases, suspended liquid and solid particles. Even though it is invisible to our eyes, it has a tremendously complex composition and it is vital for our existence. About 99% of dry air is composed of just two elements: nitrogen (78%) and oxygen (21%). The remaining percentage is a mixture of various other gases such as argon, carbon dioxide, neon, helium, methane, and krypton.
However, the composition of air is not constant. It can change depending on several factors such as altitude, climate, human activities like burning fossil fuels and natural events like volcanic eruptions. Understanding this composition and the changes it can undergo is crucial for addressing current issues such as the greenhouse effect, air pollution, and climate change.
Now, imagine if we could make a more practical and in-depth investigation on this composition of the air? How amazing would it be to explore the invisible yet essential nature of air through lab activities investigating its components and their properties? This project is a chance to do exactly that!
Hands-on Activity: “Investigating the Composition of Air”
Project Goal
Enhance the understanding of the concept of air composition and the natural and man-made factors that can change it through a practical and collaborative activity.
Project Description
In groups of 3 to 5 students, you will take on the role of researchers, conducting a series of simple experiments to observe the properties and composition of air. Along the way, you’ll be encouraged to think critically about how the composition of air can be changed, and what the implications of this might be.
Materials
- Candle and matches
- Glass jar
- Water
- Measuring tape
- Plastic bag
- Balloon
- Helium (optional)
- Needle and thread (for helium balloon)
- Baking soda and vinegar
- Small containers
- Weighing scale
Activity Steps
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Experiment 1: Demonstrating that air takes up space. Fill a plastic bag with air and measure its volume using the measuring tape. Seal it tightly and squeeze the bag. Observe and discuss what happens.
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Experiment 2: Demonstrating that air has weight. Take two balloons of the same size. Fill one with air and leave the other empty. Weigh both of them on the weighing scale and compare the results.
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Experiment 3: Demonstrating that air is a mixture of gases. Place a lighted candle inside the jar and fill it with water. Observe what happens to the candle and the water level. This is a demonstration that air is largely composed of oxygen.
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Experiment 4: Demonstrating that the composition of air can be changed. In a small container, mix baking soda and vinegar to generate carbon dioxide gas. Carefully pour the gas (not the liquid) into the jar with the burning candle. Observe and discuss what happens to the flame.
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Experiment 5: Demonstrating that different gases have different densities. Fill one balloon with air and another with helium (if available). Release both of them and observe their behavior.
Project Deliverables and Documentation
Upon completion of the experiments, each group is required to prepare a project report that should include the following sections:
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Introduction: Provide context on the composition of air, its significance, and real-world applications. Clearly state the purpose of this project.
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Development: Explain the theory behind the composition of air, describe each of the experiments conducted, the methodology used, and present the results obtained. Discuss the results and relate them to the theory.
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Conclusion: Summarize the main points of the project, reflecting on what was learned and the conclusions drawn from the experiments.
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Bibliography: Reference any sources that were consulted to complete the project such as books, web pages, videos, etc.
This project is expected to take around 5-10 hours of work for each participating student and should be completed within a month.
