Experimenting with Water

We have been learning about the water cycle.

We love the water cycle song, and the story about Drippy the Raindrop.

We know how to make our own “cloud in a bottle”, but we need your help to light the match, and to drop it into a bottle that has a couple of drops of water in it.  Now by creating an area of high and low pressure (by squeezing the bottle and then letting go) we can make a cloud that only appears when we stop squeezing.

“Water vapor, water in its invisible gaseous state, can be made to condense into the form of small cloud droplets. By adding particles such as the smoke enhances the process of water condensation and by squeezing the bottle causes the air pressure to drop. When you squeeze the bottle, the pressure increases. This causes the temperature inside the bottle to rise. When you release the bottle, the pressure decreases. This causes the temperature inside the bottle to fall and the water molecules to condense.”

We have a puzzle for the weekend.  Teacher put an octopus into a bottle of water. (She also made a similar fish from a pen cap, blue tack, a paper clip and an elastic band.)  She wants us to think of a way to get the octopus or fish to sit at the bottom of the bottle, but then to come to the top again when we want.  We already tried turning the bottle upside down, tilting the bottle, shaking the bottle, opening the top of the bottle, blowing on the octopus and taking out the air in the bottle.  Nothing seems to work.  We have our thinking caps on for the weekend!

We also tried a few bath tricks that we can do at home: we can get water to stay in an open bottle turned upside down, we can get water to stay in a yoghurt pot with just a sheet of card and we can get a ping pong ball to stay in an upside down open bottle of water.  We know why all these things work too!!