What happens to water as it freezes?

As water freezes, it expands. This is a unique property of water that sets it apart from most substances. When water cools down to 0 degrees Celsius (32 degrees Fahrenheit), it begins to form ice. As the molecules slow down, they arrange themselves into a crystalline structure that occupies more space than when the water is in its liquid state. This increased volume causes ice to be less dense than liquid water, which is why ice floats on water.

The expansion of water upon freezing is an important phenomenon in the environment. For instance, it influences the structural integrity of lakes and rivers during wintertime, affecting aquatic life and ecosystems. Understanding this behavior is crucial in fields ranging from environmental science to engineering, where the effects of freezing on water can impact various applications.