• Air that is breathed in and air that is breathed out has?different amounts of gases?in it due to exchanges that take place in the?alveoli
• Atmospheric air contains around?20 – 21% oxygen, of which we only absorb around 4 – 5%, breathing out air containing around?16% oxygen
• Normal?carbon dioxide content of air is around 0.04%?and, as carbon dioxide diffuses into the alveoli from the blood, we breathe out air containing around?4% carbon dioxide
• The air we breathe out contains?more water vapour?than when we breathe it in, and the?temperature of exhaled air is higher?than inhaled air

Composition of Air Table

轉載自savemyexams