Understanding the Change: Physical or Chemical?
When we mix water with sugar and stir, a specific type of change occurs. This process is classified as a **physical change**.

Why is it a Physical Change?
- **Definition of Physical Change**: A physical change is a transformation that alters one or more physical properties of a substance without changing its chemical composition.
- **Dissolution Process**: When sugar is added to water, the sugar molecules interact with water molecules. The water molecules surround the sugar molecules, breaking them apart and allowing them to disperse evenly throughout the solution.

Characteristics of the Change
- **No New Substance Formed**: The fundamental chemical structure of the sugar (sucrose) remains intact. No new substances are created during the process; only the state of sugar changes from solid to dissolved form.
- **Reversibility**: This change can be reversed by evaporating the water, allowing the sugar to recrystallize. This is a key characteristic of physical changes.
- **Energy Changes**: While energy may be absorbed or released (in the form of heat) during the dissolution process, it does not indicate a chemical change since the identity of the substances remains unchanged.

Conclusion
In conclusion, mixing water with sugar results in a physical change due to the dissolution of sugar in water, maintaining its chemical identity and allowing for reversibility. Understanding this distinction is crucial, especially in scientific classifications and processes.