What happens to the density of water as it warms?

As water warms, its density decreases. This phenomenon occurs because when water is heated, the molecules gain energy and move more rapidly, causing them to spread apart. As a result, the overall volume of the water increases while the mass remains the same. Since density is defined as mass per unit volume, an increase in volume while keeping mass constant leads to a decrease in density.

In natural bodies of water, this principle is observed, particularly as it relates to thermal stratification during seasonal changes. Warmer water tends to sit above cooler water because of its lower density. Thus, the relationship between temperature and density is crucial for understanding various aquatic processes and the behavior of underwater ecosystems.