Biological molecules
In astrobiology, the search for extraterrestrial life often focuses on planets or moons with liquid water beneath surface ice sheets, such as Jupiter’s moon Europa. Here, a thick outer crust of ice insulates a massive subsurface liquid ocean, which is kept warm by hydrothermal activity.
Explain how the molecular structure and hydrogen bonding of water give rise to its density and thermal properties, and outline how these properties (rather than its solvent properties) make such ice-covered oceans viable habitats for life.