Making oxygen gas
Apparatus and chemicals
- Conical flask with side arm, thistle funnel, delivery tube
- 2 gas jars/test tubes and 2 stoppers
- Basin/trough of water
- Test tube rack
- Basin/trough half-filled with water, bee hive shelf (optional, but helps to stabilise test tubes)
- Manganese dioxide/manganese(IV) oxide (3 g)
- Hydrogen peroxide solution (20 vol)
- Wooden Splint
- Carefully place the manganese(IV) oxide into the conical flask.
- Collect 50 cm3 of hydrogen peroxide solution in a small beaker.
- Connect the delivery tube and thistle funnel to the conical flask with the delivery tube in a basin of water.
- Have three test tube filled with water also inverted in the basin of water.
- Carefully pour the hydrogen peroxide solution into the thistle funnel, wait 5 s then carefully place the first water filled test-tube over the end of the delivery tube. Allow the test-tube to fill with gas (when all of the water has been displaced).
- Leave the test-tube inverted in the water to retain the gas.
- Repeat step 5 until two test tubes of gas have been collected.
- Remove each test tube from the water as required for the following tests.
Testing the gas
To the first test-tube insert a glowing splint – record your observations. Repeat with the second test-tube of gas.