Split Flame With Gauze

A Bunsen burner flame is interrupted with a piece of wire gauze. The gas burns only above the gauze, not below it. This demonstrates how the gauze conducts heat away, preventing ignition below, while hot vapors reignite above the mesh.

1. Place a piece of gauze securely on a ring stand or tripod.
2. Position a Bunsen burner so that its flame would normally pass through the gauze.
3. Turn on the gas and light it above the gauze.
4. Observe that the flame burns only above the gauze while no flame appears below.
5. Note how the gauze conducts heat away from the lower gas, cooling it below ignition temperature.

Flame Through A Gauze? - Pete's Shed:

📄 Copper gauze over flame; gas burns only above gauze - Physics @ Berkley: https://berkeleyphysicsdemos.net/node/241

• Try different mesh sizes or materials (copper, iron, steel) to compare effectiveness.
• Place a second gauze higher up to create multiple flame zones.
• Demonstrate with both candle vapor and Bunsen burner gas for comparison.

• Safety glasses required.
• Handle gauze with tongs - it becomes hot quickly.
• Keep flammable materials clear of the flame.
• Ensure the Bunsen burner is stable to prevent tipping.

• Why does the flame not appear below the gauze? (The copper conducts heat away, cooling the gas below ignition temperature.)
• Why does the flame burn above the gauze? (The rising gas meets air and retains enough heat to reignite once past the mesh.)
• How does this demonstrate the principle of conduction? (The metal gauze conducts heat rapidly, removing energy from the lower gas and preventing ignition.)
• Can this principle be used in real-world applications? (Yes, similar principles are used in flame arrestors in safety equipment.)