Materials:
* Two test tubes
* Two lit wooden splints
* Two glass beakers
* Limewater (calcium hydroxide solution)
* Oxygen gas source (e.g., oxygen cylinder or electrolysis apparatus)
* Carbon dioxide gas source (e.g., dry ice or reaction of an acid with a carbonate)
Procedure:
1. Preparation:
* Fill two test tubes with the respective gases, one with oxygen and one with carbon dioxide. Label the tubes accordingly.
* Prepare a beaker with limewater.
2. Oxygen Test:
* Step 1: Take a lit wooden splint and carefully insert it into the test tube filled with oxygen gas.
* Step 2: Observe the flame. Oxygen gas will cause the flame to burn brightly and intensely.
3. Carbon Dioxide Test:
* Step 1: Carefully pour some of the carbon dioxide gas from its test tube into the beaker containing limewater.
* Step 2: Observe the limewater. Carbon dioxide gas will cause the limewater to become cloudy or milky white.
4. Observation and Conclusion:
* Compare the results of the two tests.
* Oxygen gas: The lit splint will burn brightly in the presence of oxygen.
* Carbon dioxide gas: The limewater will turn cloudy or milky white in the presence of carbon dioxide.
Safety Precautions:
* Always handle chemicals with care. Wear appropriate safety gear like gloves and goggles.
* Work in a well-ventilated area.
* Never directly inhale any gas.
* Dispose of chemicals properly.
* Supervise children when conducting experiments.
Note: This procedure uses simple, common methods to distinguish between oxygen and carbon dioxide. More sophisticated methods exist, like using a gas chromatograph or a mass spectrometer.
