Write two properties of air.

Hint: Air is a mixture of many gases and it mainly refers to the earth's atmosphere. It is a colourless and odourless gas and it is important for all living creatures. All creatures on this earth can't live without air. The combustion reaction takes place only because of oxygen. The weight of air will lead to atmospheric pressure.

Complete step by step answer:
Air is mainly a mixture of gases like nitrogen, oxygen, etc... and thus, it forms the atmosphere. It is a mixture of invisible colourless and odourless gas. "without air, we can't live". This is because air is important for all creatures on this earth.
Atmosphere (air) consists of \[78\% \] nitrogen, \[21\% \] oxygen, \[0.93\% \] argon, \[0.03\% \] carbon dioxide and \[0.04\% \] other gases include helium ,ozone and hydrogen.
Properties of air:
Air is a colourless and odourless gas. It has mass. It exerts some space. It exerts pressure since the weight of air denotes the atmospheric pressure. It is also considered as a matter. It can be compressed and expanded. Air can be compressed at high pressure and it can be expanded by heating (increasing the temperature). It can be affected by temperature since the temperature is the main factor for the liquefaction of gases.

Note: Air is important for producing atmosphere layers. It helps in photosynthesis for plants. It also helps in the respiration process of living organisms. The combustion reaction takes place only because of oxygen. Thus, there are so many properties of air and it has been used in many ways. When we reach high altitude, we will find the region in that altitude is so cool. This is because when altitude increases, then air pressure will decrease and it makes the high-altitude locations colder than areas close to sea level.