Freezing of water is an example of which type of change?

Freezing of water is classified as a physical change because it involves a change in the state of matter without altering the chemical composition of the substance. When water freezes, it changes from a liquid to a solid due to a decrease in temperature. Throughout this process, the individual water molecules remain chemically unchanged; only their arrangement changes.

In the case of physical changes, such properties as shape, size, or state of matter can shift, but the inherent chemical properties remain intact. For example, when ice melts back into water, it can do so repeatedly, demonstrating its reversible nature. This characteristic is a hallmark of physical changes.

In contrast, a chemical change would involve a transformation that alters a substance's chemical structure, resulting in the formation of one or more new substances. For example, burning wood transforms it into ash, smoke, and gases, representing a clear chemical change. Similarly, nuclear and biochemical changes pertain to nuclear reactions and biochemical processes respectively, which are not relevant in the context of water freezing.