A chemist can view things at the macroscopic and microscopic level. The macroscopic level includes anything seen with the naked eye. The microscopic level includes atoms and molecules, things not seen with the naked eye. Both levels describe matter. Matter is anything that occupies space and has mass. However, light is not matter. It is a form of energy. Matter can be in three states: Solid, Liquid, or Gas.
A gas has NEITHER a definite volume NOR shape. At the microscopic level, a gases particles are very far apart. These particles move fast and independently of each other. Such properties allow a gas to expand inside its container.
A solid has a definite shape and definite volume. At the microscopic level, a solids particles are very close to each other. They are usually arranged into a regular pattern known as a crystal lattice.
A liquid has a definite volume but NOT a definite shape. In other words, a liquid can conform to the shape of its container. At the microscopic level, a liquids particles are farther apart from each other. Such spacing gives a liquid the ability to flow.
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