Make this easy water cycle in a bottle science experiment to illustrate how the water cycle works up close and personal. Kids will love making their own water biomes in a bottle and will be fascinated to watch the water turn into a gas, turn back into a liquid, and fall back into the bottom of the bottle.
- Plastic Bottle
- Plastic Cup
- Ice Cubes
- Blue food colouring/water colours
- Permanent Marker
1. Remove the labels from the bottles. Add a drop of blue food coloring to each bottle and fill about 1/3 of the way with water. Screw the caps on tightly.
2. Let the kids decorate their bottles with clouds, water and rain drops.
Turn the bottles upside down inside a cup.
3. Discuss the water cycle and why water evaporates and rains.
Place a couple of ice cubes on top of each bottle and set it in a sunny location.
Check the bottles after about an hour.
There should be condensation on the top of the bottle, and there may even be a small cloud there!
Watch as the droplets of water fall back to the bottom of the bottle.
Questions that you can ask your child:
- Will the water cycle occur even without the ice cube?
- What happens when you put the bottle in the sun?
- How long does your mini water cycle take to complete?
If they are not sure about the answers, ask them to repeat the experiment with the conditions stated in above questions.
The Science Behind The Water Cycle in a Bottle Science Experiment
Water has three states of matter: Liquid, gas, and solid. When liquid turns into a gas, this is called vaporization. Water when heated(in this case placed in the sun) evaporates, turns into a gas, and rises into the air. This collects water droplets at the top of the bottle, known as condensation, when gas turns back into water(Turns back to water when cooled by ice placed at the top). When the water gets heavy enough, it falls back to the bottom of the bottle just how rain falls back to earth. Water evaporating and then turning back into a solid or liquid and returning to earth is the water cycle.