Question

how can you prove that oxygen is needed for combustion​

Answer 1

Answer:

Oxygen is the most common just because it's in the air all around us.

Explanation:

Answer 2

$\huge{\mathcal{\red{HeY!}}}$

When the burning candle is covered with gas jar, then the candle takes away the oxygen necessary for burning from the air enclosed in the gas jar. After some time, when all the oxygen of air inside the gas jar is used up, then the burning candle gets extinguished.

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