<h2>Normal quiet expirarion of air is known as Tidal volume which is equal to 500 mL .</h2>
Explanation:
Normal quiet expiration or Tidal volume is a expiration of air with each normal breath . This is about 500 mL . It is composed of about 350 mL of alveolar volume and about 150 mL of dead space volume . The alveolar volume consist of the air that reaches the respiratory surface of alveoli and involve in gaseous exchange . The dead space volume consist of air that does not reach the respiratory surfaces . The lowest value is of Tidal volume . There is an extra amount of air that can be expired forcibly after a normal expiration i.e., known as expiratory reserve volume which is equal 1000 mL of air .
