Liquid

In the liquid state, particles are still closely packed, but they have enough energy to move around each other. This allows liquids to flow and take the shape of their container, although they still have a fixed volume. The forces between particles in liquids are weaker than in solids, which gives them the ability to move past one another. This is why liquids have the ability to flow and conform to the shape of their environment. Water, oil, and mercury are common examples of liquids that flow freely, taking the shape of their containers but not expanding or contracting to fill the space completely.

The behavior of liquids also depends on the type of intermolecular forces present. For example, water has hydrogen bonds between its molecules, making it a highly cohesive liquid. This cohesion leads to surface tension, a phenomenon where the surface of the liquid behaves like a stretched elastic membrane. Additionally, liquids are incompressible under normal conditions, meaning their volume remains constant even when external pressure is applied. However, they do experience slight changes in volume under extreme pressure, unlike solids.