======Cloud in a Bottle======


<WRAP right box>
**Materials: **{{$demo.materials_description}}\\
**Difficulty: **{{$demo.difficulty_description}}\\
**Safety: **{{$demo.safety_description}}\\
\\
**Categories:** {{$demo.categories}}
\\


**Alternative titles:** Mini Water Cycle Cloud
</WRAP>

====Summary====                   
{{$demo.summary}}



====Procedure====  
  - Prepare a cork or stopper with a hole through it and insert a ball inflating needle. Add a toothpick sideways to stop the cork from being pushed inside the bottle.  
  - Pour about 60 ml of rubbing alcohol into a clean, clear 2 L plastic bottle. Seal with the cork stopper.  
  - Tilt and shake the bottle to coat the inside with alcohol.  
  - Attach a bicycle pump to the stopper and pump in about four strokes of air.  
  - Quickly remove the stopper and observe the cloud forming inside the bottle.  
  - To repeat, reseal the bottle, add more air, and release again.
  - Alternatively, twist the bottle to create the pressure rather than using the bicycle pump (as shown in Links)



====Links==== 
How To Make A Cloud In A Water Bottle | Simple Cloud In A Bottle | Weather Experiment For Kids - Playing with Rain: 
{{youtube>WeXuKd0vMRk?}}\\

Science at Home - Cloud in a Bottle Experiment - The Sci Guys: 
{{youtube>23-Ks9Wy19I?}}\\

📄 Cloud in a Bottle - Science World: [[https://www.scienceworld.ca/resource/cloud-bottle/]]\\


====Variations====
  * Try with warm water instead of rubbing alcohol (the effect will be less dramatic).  
  * Compare the speed of cloud formation using different amounts of rubbing alcohol.  
  * Use a flashlight to shine through the cloud for better visibility.  
  * Record the cloud with slow-motion video to observe droplet formation more clearly.



====Safety Precautions====
  * Safety goggles required for everyone nearby.  
  * Use only a small amount of rubbing alcohol—pour excess back immediately.  
  * Do not over-pressurize the bottle—too much pressure may cause it to rupture.  
  * Point the bottle away from people when releasing the stopper, as liquid spray may occur.  





====Questions to Consider====
  * What causes the cloud to form when the stopper is released? (The sudden drop in pressure cools the vapor, causing condensation into tiny droplets.)  
  * Why do we use rubbing alcohol instead of water? (Alcohol evaporates more easily, producing a more dramatic effect.)  
  * How is this similar to cloud formation in the sky? (In both cases, rising air cools and water vapor condenses on small particles to form visible droplets.)  
  * How do temperature and pressure affect the ability of air to hold water vapor? (Warm air holds more vapor; cooling reduces capacity and leads to condensation.)