Combustion and Oxygen

The video explores whether oxygen is essential for combustion through a candle experiment. Three candles are set up with varying levels of oxygen exposure. The first candle burns freely, the second flickers and smokes before extinguishing, and the third goes out immediately. The experiment concludes that oxygen is necessary for combustion.

In the experiment, how is the first candle covered?

• With a metal cover.

• With a glass plate directly on top.

• With a glass resting on two wooden blocks.

• With a glass resting on the table.

Why is oxygen considered essential for combustion?

• It acts as a fuel.

• It supports the burning process.

• It cools down the flame.

• It provides the necessary heat.

What happens to the second candle when it is covered?

• It goes out immediately.

• It burns brighter.

• It continues to burn without change.

• The flame flickers and produces smoke before going out.

What is the outcome for the third candle when covered with a glass plate?

• It melts completely.

• It burns more intensely.

• It goes out immediately.

• It produces a lot of smoke.

What is the main conclusion drawn from the candle experiment?

• Oxygen is essential for combustion.

• Air is not necessary for combustion.

• Candles burn better without covers.

• Glass enhances the burning process.