How to Make a Cloud in Your Mouth
Description: This phenomenon can be used to show how water moves from the atmosphere to the hydrosphere. The humidity of the air in the mouth is increased by moving the tongue, releasing water from the salivary gland. The pressure in the mouth is increased and then rapidly decreased causing small droplets of water to form. The same phenomenon occurs as moist air moves up in the atmosphere eventually forming clouds. A light can be used to make the cloud more visible.
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