The air we breathe in and breathe out is not pure oxygen or carbon dioxide respectively. Although we know that our body and the cells inside it need oxygen to respire, our environment does not provide us with an exclusive supply of oxygen. In a similar way, while breathing out, we do exclusively give out carbon dioxide. Let’s different composition of gases we breathe.
Gases That We Breathe In
We are aware that our atmosphere is a mixture of gases. The atmosphere contains 78% nitrogen, 21% oxygen, 1% argon, 0.04% carbon dioxide, 0.5% water vapour. When we breathe in, we inhale the same mixture of gases contained in the atmosphere as our noses cannot filter out other gases to just take in oxygen.
The composition of the air that we breathe in also depends on our surrounding environment. For example, during respiration processes, the air inhaled by underwater divers contains more oxygen or helium. Similarly, the space suits worn by astronaut supplies pure oxygen for them to breathe in space.
Gases That We Breathe Out
Stand in front of a mirror and breath out. You will see a film of moisture appearing on the mirror surface. Have you ever wondered where do these water droplets come? It is the same air that we inhale. Remember? We have mentioned in above section that the air we breathe in contains 0.05% water vapor. Therefore, the film of moisture formed on the mirror surface is because of the water vapor content in the air.
When we exhale, the composition of the air remains almost same as the air we inhale, only the percentage of carbon dioxide and oxygen changes. The air we breathe in contains 21% oxygen and 0.04% carbon dioxide, while the air we breathe out contains 16.4% oxygen and 4.4% carbon dioxide. This is because our cells use oxygen from the inhaled air to release energy and give out carbon dioxide as a byproduct.
Stay tuned with Byju’s to learn more about Gasses.
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