Question

Why is oxygen called a gas?

Answer 1

Oxygen is gas because:

1. it neither have  fixed volume nor fixed shape.

2. oxygen is highly compressible.

3. molecules of gas are free to move.

Answer 2

Oxygen is called as a gas because it is present in the atmosphere as a in the gaseous form and constitutes about 21 percent of atmosphere.
Also we cannot see oxygen. Oxygen do not have mass and volume and also we can't measure it.

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