Can you make a cloud form inside a bottle? Fog is just a cloud that sits near the ground. It appears when warm moist air meets something cold.
You fill one bottle halfway with very hot water. Then you pour out most of the water and place an ice cube in the mouth of the bottle. You do the same with a bottle of cold water for comparison.
Watch what happens inside each bottle. The warm bottle should fill with a small fog cloud while the cold one stays clear.
Hypothesis
The hypothesis is that fog forms when warm, moist air is cooled quickly.
Fog is just a cloud that sits near the ground — and this experiment lets you make one inside a bottle. When warm, moist air meets something cold, it condenses into tiny water drops. You fill a bottle halfway with very hot water, pour out most of it, then place an ice cube in the mouth. As the moist air inside cools quickly, a small fog cloud forms. The cold bottle, filled with cold water from the start, stays clear because there is no warm, moist air to cool down.
Clouds form when warm, moist air cools and tiny water drops appear. In this experiment, hot water fills a bottle with warm, moist air. When an ice cube cools that air quickly, a small fog cloud forms inside the bottle.
Fog is a cloud that sits near the ground, appearing when warm moist air meets something cold. In this experiment, you fill a bottle with very hot water, pour most of it out, then place an ice cube in the mouth of the bottle. Watch what happens: the warm, moist air inside cools down fast, and a small fog cloud forms within the bottle. A cold water bottle held alongside stays clear, showing exactly what that temperature difference does.
Method & Materials
You will fill one bottle with hot water and the other with cold water, pour out the hot water, and then place an ice cube in the mouth of each bottle.
You will need two bottles, hot and cold water, and an ice cube.
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After the experiment, you will observe that the warm, moist air in the bottle with hot water is cooled quickly and forms fog. The fog is denser in the bottle with hot water than in the bottle with cold water.
Why do this project?
This science project is so interesting and unique because it allows you to observe the formation of fog in a controlled environment.
Also Consider
Experiment variations to consider include using different temperatures of water and different sizes of ice cubes.
Full project details
Additional information and source material for this project are available below.
