As temperature increases, heavy water to light water ratios also increase. There are also other properties that are different for heavy water and light water. In the image below, notice that, in water, ice made from heavy water (left beaker) will sink but ice made from light water (right beaker) will float. But, at the molecular level, what makes heavy water and light water different?

Chemistry concepts, such as the basic structure of the atom, can help us understand the difference between heavy water and light water.