AP Bio Water Lab

Station 4: Density of water.

In this lab we used a pipette to put cold water that was dyed green into another beaker of room temperature water to test how the density of water affects the way it interacts with each other. The colder water sunk to he bottom while the warmer water went above it, we could see this happen because the colder, green dyed water sifted itself to the bottom of the beaker. Heat rises, so naturally the warmer water is less dense than the colder water.

 Station 6: polar solvent

In this experiment, we tested whether water solvents conducted electricity with salt or with sugar. With salt, the water was able to conduct electricity. However, the sugar water couldn't. Salt was able to conduct because when salt (NaCl) is dissolved in water, it loses an electron to chloride. Since sugar  doesn't conduct electricity, it proves that its ions do not bounce around.

Station 1: polarity in water molecules

In this lab, we dropped water drop by drop onto a penny and discovered the water molecules were polar and clung together but once we poked it with a toothpick covered in soap, the water dispersed due to the non polarity from the soap.