Question

A list of words is given in a box. Use appropriate words to fill up the blanks in the following statements.

[Air, oxygen, wind, water vapor, mixture, combination, direction, road, bottles, cylinders]

Air is a ______ of some gases.

Answer 1

Air:

The term "air" refers to the gas combination that makes up the Earth's atmosphere.

1. This gas is principally composed of Nitrogen $(78\%)$combined with Oxygen $(21\%)$, Water vapor (variable), Argon $(0.9\%)$, Carbon dioxide $(0.04\%)$, and trace gases.
2. There is no visible fragrance or color in pure air.
3. Dust, pollen, and spores are common pollutants in the air; additional contaminants are referred to as "air pollution."
4. Because there is no air in space, the so-called air on another planet, such as Mars, would have a different composition.

Thus, the air is a mixture of some gases.