Final answer:
In a liquid, particles are close together with no fixed arrangement, allowing them to slide past each other and flow. They have enough energy to move about freely while maintaining a definite volume but no fixed shape, and the substance takes the shape of its container.
Step-by-step explanation:
Particle Arrangement and Behavior in Liquids
In the liquid state, the particle arrangement does not have a regular pattern, as it might in a solid. The particles, which can be atoms, molecules, or ions, are still in close proximity, which results in liquids having a definite volume. Despite the closeness of the particles, they have enough energy to partially overcome intermolecular attractions and can move freely past each other. This freedom of movement allows liquids to take on the shape of their containers and to flow, which defines many of their characteristics. Liquids also exhibit properties such as surface tension, as seen in substances like mercury.
According to the kinetic molecular theory, the particles in a liquid remain in essentially constant contact while being free to change neighbors. This contrasts with the behavior in a solid, where particles vibrate around fixed positions, and in a gas, where particles have much more space to move independently.