Will water vapour decrease in amount after being exhaled by a human and before it was inhaled human?
The amount of water vapour in the air will increase after being exhaled by a human and before it was inhaled by a human.
When a human exhales, they release warm, moist air into the atmosphere. This air contains a higher concentration of water vapour than the air that was inhaled, as the lungs add moisture to the air as it passes through them. As this exhaled air cools, the water vapour condenses into tiny droplets, forming visible water vapour in the form of fog or mist.
When a human inhales, they draw in this moist air and the water vapour is absorbed by the lungs, humidifying the air and increasing the body's hydration.