investigating the attraction of water molecules…

jan. 2009
This was a fun science project. We took a dropper, and drop by drop, counted how many the quarter would hold before spilling off. The water bubbles over the quarter, because the water molecules attract each other. Then when the bubble can no longer hold itself on, it spills off to the side, pulling all the water off together.

When introducing dishwashing soap, it breaks the molecular binding of the water, causing a lesser amount of droplets to stay on the quarter.

The next experiment we did, we had a bowl of water, and set a paper clip on a fork, lowering it into the water. The paper clip would float, because the water molecules were so tightly stuck together, they would not let the paperclip drop into the water.

We then added dishwashing soap to the bowl of water, lowered the paperclip in atop the fork, just like the first time, and the paperclip dropped. For the same reason as we did in the first experiment, the soap molecules get between the water molecules, and prevent the water molecules from sticking together. Easy experiment, and lots of fun!