Hydrometer

Build a Hydrometer:

     We built a hydrometer using zinc balls. We had a beaker of tap water and cut the top off of a plastic dropper so that the zinc balls would fit in the dropper. We added zinc until the plastic dropper stood straight up in the water, without it touching the bottom. After it was balanced, we added zinc until it floated to the bottom of the beaker. After adding enough salt to the water, the hydrometer started to float again. We did this experiment to show how the salinity of the water affects how the properties change. In salt water, heavier items float better.

1. salinity: relating to salts, salty
2. It will float higher.
3. H2O --->H2ONaCl
4. In the ocean
5. density: mass/volume
6. When its warmer more

Tears of an Ocean Planet: